<!-- doc/src/sgml/release-9.3.sgml -->
<!-- See header comment in release.sgml about typical markup -->

 <sect1 id="release-9-3-24">
  <title>Release 9.3.24</title>

  <formalpara>
  <title>Release date:</title>
  <para>2018-08-09</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.23.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <para>
   The <productname>PostgreSQL</productname> community will stop releasing
   updates for the 9.3.X release series shortly after September 2018.
   Users are encouraged to update to a newer release branch soon.
  </para>

  <sect2>
   <title>Migration to Version 9.3.24</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.23,
    see <xref linkend="release-9-3-23"/>.
   </para>
  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix failure to reset <application>libpq</application>'s state fully
      between connection attempts (Tom Lane)
     </para>

     <para>
      An unprivileged user of <filename>dblink</filename>
      or <filename>postgres_fdw</filename> could bypass the checks intended
      to prevent use of server-side credentials, such as
      a <filename>~/.pgpass</filename> file owned by the operating-system
      user running the server.  Servers allowing peer authentication on
      local connections are particularly vulnerable.  Other attacks such
      as SQL injection into a <filename>postgres_fdw</filename> session
      are also possible.
      Attacking <filename>postgres_fdw</filename> in this way requires the
      ability to create a foreign server object with selected connection
      parameters, but any user with access to <filename>dblink</filename>
      could exploit the problem.
      In general, an attacker with the ability to select the connection
      parameters for a <application>libpq</application>-using application
      could cause mischief, though other plausible attack scenarios are
      harder to think of.
      Our thanks to Andrew Krasichkov for reporting this issue.
      (CVE-2018-10915)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that updates to the <structfield>relfrozenxid</structfield>
      and <structfield>relminmxid</structfield> values
      for <quote>nailed</quote> system catalogs are processed in a timely
      fashion (Andres Freund)
     </para>

     <para>
      Overoptimistic caching rules could prevent these updates from being
      seen by other sessions, leading to spurious errors and/or data
      corruption.  The problem was significantly worse for shared catalogs,
      such as <structname>pg_authid</structname>, because the stale cache
      data could persist into new sessions as well as existing ones.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix case where a freshly-promoted standby crashes before having
      completed its first post-recovery checkpoint (Michael Paquier, Kyotaro
      Horiguchi, Pavan Deolasee, &Aacute;lvaro Herrera)
     </para>

     <para>
      This led to a situation where the server did not think it had reached
      a consistent database state during subsequent WAL replay, preventing
      restart.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid emitting a bogus WAL record when recycling an all-zero btree
      page (Amit Kapila)
     </para>

     <para>
      This mistake has been seen to cause assertion failures, and
      potentially it could result in unnecessary query cancellations on hot
      standby servers.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve performance of WAL replay for transactions that drop many
      relations (Fujii Masao)
     </para>

     <para>
      This change reduces the number of times that shared buffers are
      scanned, so that it is of most benefit when that setting is large.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve performance of lock releasing in standby server WAL replay
      (Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure a table's cached index list is correctly rebuilt after an index
      creation fails partway through (Peter Geoghegan)
     </para>

     <para>
      Previously, the failed index's OID could remain in the list, causing
      problems later in the same session.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix misoptimization of equivalence classes involving composite-type
      columns (Tom Lane)
     </para>

     <para>
      This resulted in failure to recognize that an index on a composite
      column could provide the sort order needed for a mergejoin on that
      column.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix SQL-standard <literal>FETCH FIRST</literal> syntax to allow
      parameters (<literal>$<replaceable>n</replaceable></literal>), as the
      standard expects (Andrew Gierth)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix failure to schema-qualify some object names
      in <function>getObjectDescription</function> output
      (Kyotaro Horiguchi, Tom Lane)
     </para>

     <para>
      Names of collations, conversions, and text search objects
      were not schema-qualified when they should be.
     </para>
    </listitem>

    <listitem>
     <para>
      Widen <command>COPY FROM</command>'s current-line-number counter
      from 32 to 64 bits (David Rowley)
     </para>

     <para>
      This avoids two problems with input exceeding 4G lines: <literal>COPY
      FROM WITH HEADER</literal> would drop a line every 4G lines, not only
      the first line, and error reports could show a wrong line number.
     </para>
    </listitem>

    <listitem>
     <para>
      Add a string freeing function
      to <application>ecpg</application>'s <filename>pgtypes</filename>
      library, so that cross-module memory management problems can be
      avoided on Windows (Takayuki Tsunakawa)
     </para>

     <para>
      On Windows, crashes can ensue if the <function>free</function> call
      for a given chunk of memory is not made from the same DLL
      that <function>malloc</function>'ed the memory.
      The <filename>pgtypes</filename> library sometimes returns strings
      that it expects the caller to free, making it impossible to follow
      this rule.  Add a <function>PGTYPESchar_free()</function> function
      that just wraps <function>free</function>, allowing applications
      to follow this rule.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application>'s support for <type>long
      long</type> variables on Windows, as well as other platforms that
      declare <function>strtoll</function>/<function>strtoull</function>
      nonstandardly or not at all (Dang Minh Huong, Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix misidentification of SQL statement type in PL/pgSQL, when a rule
      change causes a change in the semantics of a statement intra-session
      (Tom Lane)
     </para>

     <para>
      This error led to assertion failures, or in rare cases, failure to
      enforce the <literal>INTO STRICT</literal> option as expected.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix password prompting in client programs so that echo is properly
      disabled on Windows when <literal>stdin</literal> is not the
      terminal (Matthew Stickney)
     </para>
    </listitem>

    <listitem>
     <para>
      Further fix mis-quoting of values for list-valued GUC variables in
      dumps (Tom Lane)
     </para>

     <para>
      The previous fix for quoting of <varname>search_path</varname> and
      other list-valued variables in <application>pg_dump</application>
      output turned out to misbehave for empty-string list elements, and it
      risked truncation of long file paths.
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_upgrade</application> check that the old server
      was shut down cleanly (Bruce Momjian)
     </para>

     <para>
      The previous check could be fooled by an immediate-mode shutdown.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix crash in <filename>contrib/ltree</filename>'s
      <function>lca()</function> function when the input array is empty
      (Pierre Ducroquet)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix various error-handling code paths in which an incorrect error code
      might be reported (Michael Paquier, Tom Lane, Magnus Hagander)
     </para>
    </listitem>

    <listitem>
     <para>
      Rearrange makefiles to ensure that programs link to freshly-built
      libraries (such as <filename>libpq.so</filename>) rather than ones
      that might exist in the system library directories (Tom Lane)
     </para>

     <para>
      This avoids problems when building on platforms that supply old copies
      of <productname>PostgreSQL</productname> libraries.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application>
      release 2018e for DST law changes in North Korea, plus historical
      corrections for Czechoslovakia.
     </para>

     <para>
      This update includes a redefinition of <quote>daylight savings</quote>
      in Ireland, as well as for some past years in Namibia and
      Czechoslovakia.  In those jurisdictions, legally standard time is
      observed in summer, and daylight savings time in winter, so that the
      daylight savings offset is one hour behind standard time not one hour
      ahead.  This does not affect either the actual UTC offset or the
      timezone abbreviations in use; the only known effect is that
      the <structfield>is_dst</structfield> column in
      the <structname>pg_timezone_names</structname> view will now be true
      in winter and false in summer in these cases.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-23">
  <title>Release 9.3.23</title>

  <formalpara>
  <title>Release date:</title>
  <para>2018-05-10</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.22.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.23</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if the function marking mistakes mentioned in the first
    changelog entry below affect you, you will want to take steps to
    correct your database catalogs.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.22,
    see <xref linkend="release-9-3-22"/>.
   </para>
  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix incorrect volatility markings on a few built-in functions
      (Thomas Munro, Tom Lane)
     </para>

     <para>
      The functions
      <function>query_to_xml</function>,
      <function>cursor_to_xml</function>,
      <function>cursor_to_xmlschema</function>,
      <function>query_to_xmlschema</function>, and
      <function>query_to_xml_and_xmlschema</function>
      should be marked volatile because they execute user-supplied queries
      that might contain volatile operations.  They were not, leading to a
      risk of incorrect query optimization.  This has been repaired for new
      installations by correcting the initial catalog data, but existing
      installations will continue to contain the incorrect markings.
      Practical use of these functions seems to pose little hazard, but in
      case of trouble, it can be fixed by manually updating these
      functions' <structname>pg_proc</structname> entries, for example
      <literal>ALTER FUNCTION pg_catalog.query_to_xml(text, boolean,
      boolean, text) VOLATILE</literal>.  (Note that that will need to be
      done in each database of the installation.)  Another option is
      to <application>pg_upgrade</application> the database to a version
      containing the corrected initial data.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid re-using TOAST value OIDs that match dead-but-not-yet-vacuumed
      TOAST entries (Pavan Deolasee)
     </para>

     <para>
      Once the OID counter has wrapped around, it's possible to assign a
      TOAST value whose OID matches a previously deleted entry in the same
      TOAST table.  If that entry were not yet vacuumed away, this resulted
      in <quote>unexpected chunk number 0 (expected 1) for toast
      value <replaceable>nnnnn</replaceable></quote> errors, which would
      persist until the dead entry was removed
      by <command>VACUUM</command>.  Fix by not selecting such OIDs when
      creating a new TOAST entry.
     </para>
    </listitem>

    <listitem>
     <para>
      Change <command>ANALYZE</command>'s algorithm for updating
      <structname>pg_class</structname>.<structfield>reltuples</structfield>
      (David Gould)
     </para>

     <para>
      Previously, pages not actually scanned by <command>ANALYZE</command>
      were assumed to retain their old tuple density.  In a large table
      where <command>ANALYZE</command> samples only a small fraction of the
      pages, this meant that the overall tuple density estimate could not
      change very much, so that <structfield>reltuples</structfield> would
      change nearly proportionally to changes in the table's physical size
      (<structfield>relpages</structfield>) regardless of what was actually
      happening in the table.  This has been observed to result
      in <structfield>reltuples</structfield> becoming so much larger than
      reality as to effectively shut off autovacuuming.  To fix, assume
      that <command>ANALYZE</command>'s sample is a statistically unbiased
      sample of the table (as it should be), and just extrapolate the
      density observed within those pages to the whole table.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <literal>UPDATE/DELETE ... WHERE CURRENT OF</literal> to not fail
      when the referenced cursor uses an index-only-scan plan (Yugo Nagata,
      Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect planning of join clauses pushed into parameterized
      paths (Andrew Gierth, Tom Lane)
     </para>

     <para>
      This error could result in misclassifying a condition as
      a <quote>join filter</quote> for an outer join when it should be a
      plain <quote>filter</quote> condition, leading to incorrect join
      output.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix misoptimization of <literal>CHECK</literal> constraints having
      provably-NULL subclauses of
      top-level <literal>AND</literal>/<literal>OR</literal> conditions
      (Tom Lane, Dean Rasheed)
     </para>

     <para>
      This could, for example, allow constraint exclusion to exclude a
      child table that should not be excluded from a query.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid failure if a query-cancel or session-termination interrupt
      occurs while committing a prepared transaction (Stas Kelvich)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix query-lifespan memory leakage in repeatedly executed hash joins
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix overly strict sanity check
      in <function>heap_prepare_freeze_tuple</function>
      (&Aacute;lvaro Herrera)
     </para>

     <para>
      This could result in incorrect <quote>cannot freeze committed
      xmax</quote> failures in databases that have
      been <application>pg_upgrade</application>'d from 9.2 or earlier.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent dangling-pointer dereference when a C-coded before-update row
      trigger returns the <quote>old</quote> tuple (Rushabh Lathia)
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce locking during autovacuum worker scheduling (Jeff Janes)
     </para>

     <para>
      The previous behavior caused drastic loss of potential worker
      concurrency in databases with many tables.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure client hostname is copied while copying
      <structname>pg_stat_activity</structname> data to local memory
      (Edmund Horner)
     </para>

     <para>
      Previously the supposedly-local snapshot contained a pointer into
      shared memory, allowing the client hostname column to change
      unexpectedly if any existing session disconnected.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect processing of multiple compound affixes
      in <literal>ispell</literal> dictionaries (Arthur Zakirov)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix collation-aware searches (that is, indexscans using inequality
      operators) in SP-GiST indexes on text columns (Tom Lane)
     </para>

     <para>
      Such searches would return the wrong set of rows in most non-C
      locales.
     </para>
    </listitem>

    <listitem>
     <para>
      Count the number of index tuples correctly during initial build of an
      SP-GiST index (Tomas Vondra)
     </para>

     <para>
      Previously, the tuple count was reported to be the same as that of
      the underlying table, which is wrong if the index is partial.
     </para>
    </listitem>

    <listitem>
     <para>
      Count the number of index tuples correctly during vacuuming of a
      GiST index (Andrey Borodin)
     </para>

     <para>
      Previously it reported the estimated number of heap tuples,
      which might be inaccurate, and is certainly wrong if the
      index is partial.
     </para>
    </listitem>

    <listitem>
     <para>
      Allow <function>scalarltsel</function>
      and <function>scalargtsel</function> to be used on non-core datatypes
      (Tomas Vondra)
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce <application>libpq</application>'s memory consumption when a
      server error is reported after a large amount of query output has
      been collected (Tom Lane)
     </para>

     <para>
      Discard the previous output before, not after, processing the error
      message.  On some platforms, notably Linux, this can make a
      difference in the application's subsequent memory footprint.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix double-free crashes in <application>ecpg</application>
      (Patrick Krecker, Jeevan Ladhe)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application> to handle <type>long long
      int</type> variables correctly in MSVC builds (Michael Meskes,
      Andrew Gierth)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix mis-quoting of values for list-valued GUC variables in dumps
      (Michael Paquier, Tom Lane)
     </para>

     <para>
      The <varname>local_preload_libraries</varname>,
      <varname>session_preload_libraries</varname>,
      <varname>shared_preload_libraries</varname>,
      and <varname>temp_tablespaces</varname> variables were not correctly
      quoted in <application>pg_dump</application> output.  This would
      cause problems if settings for these variables appeared in
      <command>CREATE FUNCTION ... SET</command> or <command>ALTER
      DATABASE/ROLE ... SET</command> clauses.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix overflow handling in <application>PL/pgSQL</application>
      integer <command>FOR</command> loops (Tom Lane)
     </para>

     <para>
      The previous coding failed to detect overflow of the loop variable
      on some non-gcc compilers, leading to an infinite loop.
     </para>
    </listitem>

    <listitem>
     <para>
      Adjust <application>PL/Python</application> regression tests to pass
      under Python 3.7 (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Support testing <application>PL/Python</application> and related
      modules when building with Python 3 and MSVC (Andrew Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      Rename internal <function>b64_encode</function>
      and <function>b64_decode</function> functions to avoid conflict with
      Solaris 11.4 built-in functions (Rainer Orth)
     </para>
    </listitem>

    <listitem>
     <para>
      Sync our copy of the timezone library with IANA tzcode release 2018e
      (Tom Lane)
     </para>

     <para>
      This fixes the <application>zic</application> timezone data compiler
      to cope with negative daylight-savings offsets.  While
      the <productname>PostgreSQL</productname> project will not
      immediately ship such timezone data, <application>zic</application>
      might be used with timezone data obtained directly from IANA, so it
      seems prudent to update <application>zic</application> now.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application>
      release 2018d for DST law changes in Palestine and Antarctica (Casey
      Station), plus historical corrections for Portugal and its colonies,
      as well as Enderbury, Jamaica, Turks &amp; Caicos Islands, and
      Uruguay.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-22">
  <title>Release 9.3.22</title>

  <formalpara>
  <title>Release date:</title>
  <para>2018-03-01</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.21.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.22</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you run an installation in which not all users are mutually
    trusting, or if you maintain an application or extension that is
    intended for use in arbitrary situations, it is strongly recommended
    that you read the documentation changes described in the first changelog
    entry below, and take suitable steps to ensure that your installation or
    code is secure.
   </para>

   <para>
    Also, the changes described in the second changelog entry below may
    cause functions used in index expressions or materialized views to fail
    during auto-analyze, or when reloading from a dump.  After upgrading,
    monitor the server logs for such problems, and fix affected functions.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.18,
    see <xref linkend="release-9-3-18"/>.
   </para>
  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Document how to configure installations and applications to guard
      against search-path-dependent trojan-horse attacks from other users
      (Noah Misch)
     </para>

     <para>
      Using a <varname>search_path</varname> setting that includes any
      schemas writable by a hostile user enables that user to capture
      control of queries and then run arbitrary SQL code with the
      permissions of the attacked user.  While it is possible to write
      queries that are proof against such hijacking, it is notationally
      tedious, and it's very easy to overlook holes.  Therefore, we now
      recommend configurations in which no untrusted schemas appear in
      one's search path.  Relevant documentation appears in
      <xref linkend="ddl-schemas-patterns"/> (for database administrators and users),
      <xref linkend="libpq-connect"/> (for application authors),
      <xref linkend="extend-extensions-style"/>  (for extension authors), and
      <xref linkend="sql-createfunction"/> (for authors
      of <literal>SECURITY DEFINER</literal> functions).
      (CVE-2018-1058)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid use of insecure <varname>search_path</varname> settings
      in <application>pg_dump</application> and other client programs
      (Noah Misch, Tom Lane)
     </para>

     <para>
      <application>pg_dump</application>,
      <application>pg_upgrade</application>,
      <application>vacuumdb</application> and
      other <productname>PostgreSQL</productname>-provided applications were
      themselves vulnerable to the type of hijacking described in the previous
      changelog entry; since these applications are commonly run by
      superusers, they present particularly attractive targets.  To make them
      secure whether or not the installation as a whole has been secured,
      modify them to include only the <structname>pg_catalog</structname>
      schema in their <varname>search_path</varname> settings.
      Autovacuum worker processes now do the same, as well.
     </para>

     <para>
      In cases where user-provided functions are indirectly executed by
      these programs &mdash; for example, user-provided functions in index
      expressions &mdash; the tighter <varname>search_path</varname> may
      result in errors, which will need to be corrected by adjusting those
      user-provided functions to not assume anything about what search path
      they are invoked under.  That has always been good practice, but now
      it will be necessary for correct behavior.
      (CVE-2018-1058)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix misbehavior of concurrent-update rechecks with CTE references
      appearing in subplans (Tom Lane)
     </para>

     <para>
      If a CTE (<literal>WITH</literal> clause reference) is used in an
      InitPlan or SubPlan, and the query requires a recheck due to trying
      to update or lock a concurrently-updated row, incorrect results could
      be obtained.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix planner failures with overlapping mergejoin clauses in an outer
      join (Tom Lane)
     </para>

     <para>
      These mistakes led to <quote>left and right pathkeys do not match in
      mergejoin</quote> or <quote>outer pathkeys do not match
      mergeclauses</quote> planner errors in corner cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Repair <application>pg_upgrade</application>'s failure to
      preserve <structfield>relfrozenxid</structfield> for materialized
      views (Tom Lane, Andres Freund)
     </para>

     <para>
      This oversight could lead to data corruption in materialized views
      after an upgrade, manifesting as <quote>could not access status of
      transaction</quote> or <quote>found xmin from before
      relfrozenxid</quote> errors.  The problem would be more likely to
      occur in seldom-refreshed materialized views, or ones that were
      maintained only with <command>REFRESH MATERIALIZED VIEW
      CONCURRENTLY</command>.
     </para>

     <para>
      If such corruption is observed, it can be repaired by refreshing the
      materialized view (without <literal>CONCURRENTLY</literal>).
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect reporting of PL/Python function names in
      error <literal>CONTEXT</literal> stacks (Tom Lane)
     </para>

     <para>
      An error occurring within a nested PL/Python function call (that is,
      one reached via a SPI query from another PL/Python function) would
      result in a stack trace showing the inner function's name twice,
      rather than the expected results.  Also, an error in a nested
      PL/Python <literal>DO</literal> block could result in a null pointer
      dereference crash on some platforms.
     </para>
    </listitem>

    <listitem>
     <para>
      Allow <filename>contrib/auto_explain</filename>'s
      <varname>log_min_duration</varname> setting to range up
      to <literal>INT_MAX</literal>, or about 24 days instead of 35 minutes
      (Tom Lane)
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-21">
  <title>Release 9.3.21</title>

  <formalpara>
  <title>Release date:</title>
  <para>2018-02-08</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.20.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.21</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.18,
    see <xref linkend="release-9-3-18"/>.
   </para>
  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Ensure that all temporary files made
      by <application>pg_upgrade</application> are non-world-readable
      (Tom Lane, Noah Misch)
     </para>

     <para>
      <application>pg_upgrade</application> normally restricts its
      temporary files to be readable and writable only by the calling user.
      But the temporary file containing <literal>pg_dumpall -g</literal>
      output would be group- or world-readable, or even writable, if the
      user's <literal>umask</literal> setting allows.  In typical usage on
      multi-user machines, the <literal>umask</literal> and/or the working
      directory's permissions would be tight enough to prevent problems;
      but there may be people using <application>pg_upgrade</application>
      in scenarios where this oversight would permit disclosure of database
      passwords to unfriendly eyes.
      (CVE-2018-1053)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix vacuuming of tuples that were updated while key-share locked
      (Andres Freund, &Aacute;lvaro Herrera)
     </para>

     <para>
      In some cases <command>VACUUM</command> would fail to remove such
      tuples even though they are now dead, leading to assorted data
      corruption scenarios.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix inadequate buffer locking in some LSN fetches (Jacob Champion,
      Asim Praveen, Ashwin Agrawal)
     </para>

     <para>
      These errors could result in misbehavior under concurrent load.
      The potential consequences have not been characterized fully.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid unnecessary failure in a query on an inheritance tree that
      occurs concurrently with some child table being removed from the tree
      by <command>ALTER TABLE NO INHERIT</command> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Repair failure with correlated sub-<literal>SELECT</literal>
      inside <literal>VALUES</literal> inside a <literal>LATERAL</literal>
      subquery (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <quote>could not devise a query plan for the given query</quote>
      planner failure for some cases involving nested <literal>UNION
      ALL</literal> inside a lateral subquery (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>has_sequence_privilege()</function> to
      support <literal>WITH GRANT OPTION</literal> tests,
      as other privilege-testing functions do (Joe Conway)
     </para>
    </listitem>

    <listitem>
     <para>
      In databases using UTF8 encoding, ignore any XML declaration that
      asserts a different encoding (Pavel Stehule, Noah Misch)
     </para>

     <para>
      We always store XML strings in the database encoding, so allowing
      libxml to act on a declaration of another encoding gave wrong results.
      In encodings other than UTF8, we don't promise to support non-ASCII
      XML data anyway, so retain the previous behavior for bug compatibility.
      This change affects only <function>xpath()</function> and related
      functions; other XML code paths already acted this way.
     </para>
    </listitem>

    <listitem>
     <para>
      Provide for forward compatibility with future minor protocol versions
      (Robert Haas, Badrul Chowdhury)
     </para>

     <para>
      Up to now, <productname>PostgreSQL</productname> servers simply
      rejected requests to use protocol versions newer than 3.0, so that
      there was no functional difference between the major and minor parts
      of the protocol version number.  Allow clients to request versions 3.x
      without failing, sending back a message showing that the server only
      understands 3.0.  This makes no difference at the moment, but
      back-patching this change should allow speedier introduction of future
      minor protocol upgrades.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent stack-overflow crashes when planning extremely deeply
      nested set operations
      (<literal>UNION</literal>/<literal>INTERSECT</literal>/<literal>EXCEPT</literal>)
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix null-pointer crashes for some types of LDAP URLs appearing
      in <filename>pg_hba.conf</filename> (Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix sample <function>INSTR()</function> functions in the PL/pgSQL
      documentation (Yugo Nagata, Tom Lane)
     </para>

     <para>
      These functions are stated to
      be <trademark class="registered">Oracle</trademark> compatible, but
      they weren't exactly.  In particular, there was a discrepancy in the
      interpretation of a negative third parameter: Oracle thinks that a
      negative value indicates the last place where the target substring can
      begin, whereas our functions took it as the last place where the
      target can end.  Also, Oracle throws an error for a zero or negative
      fourth parameter, whereas our functions returned zero.
     </para>

     <para>
      The sample code has been adjusted to match Oracle's behavior more
      precisely.  Users who have copied this code into their applications
      may wish to update their copies.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> to make ACL (permissions),
      comment, and security label entries reliably identifiable in archive
      output formats (Tom Lane)
     </para>

     <para>
      The <quote>tag</quote> portion of an ACL archive entry was usually
      just the name of the associated object.  Make it start with the object
      type instead, bringing ACLs into line with the convention already used
      for comment and security label archive entries.  Also, fix the
      comment and security label entries for the whole database, if present,
      to make their tags start with <literal>DATABASE</literal> so that they
      also follow this convention.  This prevents false matches in code that
      tries to identify large-object-related entries by seeing if the tag
      starts with <literal>LARGE OBJECT</literal>.  That could have resulted
      in misclassifying entries as data rather than schema, with undesirable
      results in a schema-only or data-only dump.
     </para>

     <para>
      Note that this change has user-visible results in the output
      of <command>pg_restore --list</command>.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>ecpg</application>, detect indicator arrays that do
      not have the correct length and report an error (David Rader)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid triggering a libc assertion
      in <filename>contrib/hstore</filename>, due to use
      of <function>memcpy()</function> with equal source and destination
      pointers (Tomas Vondra)
     </para>
    </listitem>

    <listitem>
     <para>
      Provide modern examples of how to auto-start Postgres on macOS
      (Tom Lane)
     </para>

     <para>
      The scripts in <filename>contrib/start-scripts/osx</filename> use
      infrastructure that's been deprecated for over a decade, and which no
      longer works at all in macOS releases of the last couple of years.
      Add a new subdirectory <filename>contrib/start-scripts/macos</filename>
      containing scripts that use the newer <application>launchd</application>
      infrastructure.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect selection of configuration-specific libraries for
      OpenSSL on Windows (Andrew Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      Support linking to MinGW-built versions of libperl (Noah Misch)
     </para>

     <para>
      This allows building PL/Perl with some common Perl distributions for
      Windows.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix MSVC build to test whether 32-bit libperl
      needs <literal>-D_USE_32BIT_TIME_T</literal> (Noah Misch)
     </para>

     <para>
      Available Perl distributions are inconsistent about what they expect,
      and lack any reliable means of reporting it, so resort to a build-time
      test on what the library being used actually does.
     </para>
    </listitem>

    <listitem>
     <para>
      On Windows, install the crash dump handler earlier in postmaster
      startup (Takayuki Tsunakawa)
     </para>

     <para>
      This may allow collection of a core dump for some early-startup
      failures that did not produce a dump before.
     </para>
    </listitem>

    <listitem>
     <para>
      On Windows, avoid encoding-conversion-related crashes when emitting
      messages very early in postmaster startup (Takayuki Tsunakawa)
     </para>
    </listitem>

    <listitem>
     <para>
      Use our existing Motorola 68K spinlock code on OpenBSD as
      well as NetBSD (David Carlier)
     </para>
    </listitem>

    <listitem>
     <para>
      Add support for spinlocks on Motorola 88K (David Carlier)
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application>
      release 2018c for DST law changes in Brazil, Sao Tome and Principe,
      plus historical corrections for Bolivia, Japan, and South Sudan.
      The <literal>US/Pacific-New</literal> zone has been removed (it was
      only an alias for <literal>America/Los_Angeles</literal> anyway).
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-20">
  <title>Release 9.3.20</title>

  <formalpara>
  <title>Release date:</title>
  <para>2017-11-09</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.19.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.20</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.18,
    see <xref linkend="release-9-3-18"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix crash due to rowtype mismatch
      in <function>json{b}_populate_recordset()</function>
      (Michael Paquier, Tom Lane)
     </para>

     <para>
      These functions used the result rowtype specified in the <literal>FROM
      ... AS</literal> clause without checking that it matched the actual
      rowtype of the supplied tuple value.  If it didn't, that would usually
      result in a crash, though disclosure of server memory contents seems
      possible as well.
      (CVE-2017-15098)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix sample server-start scripts to become <literal>$PGUSER</literal>
      before opening <literal>$PGLOG</literal> (Noah Misch)
     </para>

     <para>
      Previously, the postmaster log file was opened while still running as
      root.  The database owner could therefore mount an attack against
      another system user by making <literal>$PGLOG</literal> be a symbolic
      link to some other file, which would then become corrupted by appending
      log messages.
     </para>

     <para>
      By default, these scripts are not installed anywhere.  Users who have
      made use of them will need to manually recopy them, or apply the same
      changes to their modified versions.  If the
      existing <literal>$PGLOG</literal> file is root-owned, it will need to
      be removed or renamed out of the way before restarting the server with
      the corrected script.
      (CVE-2017-12172)
     </para>
    </listitem>

    <listitem>
     <para>
      Properly reject attempts to convert infinite float values to
      type <type>numeric</type> (Tom Lane, KaiGai Kohei)
     </para>

     <para>
      Previously the behavior was platform-dependent.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix corner-case crashes when columns have been added to the end of a
      view (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Record proper dependencies when a view or rule
      contains <structname>FieldSelect</structname>
      or <structname>FieldStore</structname> expression nodes (Tom Lane)
     </para>

     <para>
      Lack of these dependencies could allow a column or data
      type <command>DROP</command> to go through when it ought to fail,
      thereby causing later uses of the view or rule to get errors.
      This patch does not do anything to protect existing views/rules,
      only ones created in the future.
     </para>
    </listitem>

    <listitem>
     <para>
      Correctly detect hashability of range data types (Tom Lane)
     </para>

     <para>
      The planner mistakenly assumed that any range type could be hashed
      for use in hash joins or hash aggregation, but actually it must check
      whether the range's subtype has hash support.  This does not affect any
      of the built-in range types, since they're all hashable anyway.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix low-probability loss of <command>NOTIFY</command> messages due to
      XID wraparound (Marko Tiikkaja, Tom Lane)
     </para>

     <para>
      If a session executed no queries, but merely listened for
      notifications, for more than 2 billion transactions, it started to miss
      some notifications from concurrently-committing transactions.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent low-probability crash in processing of nested trigger firings
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Correctly restore the umask setting when file creation fails
      in <command>COPY</command> or <function>lo_export()</function>
      (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Give a better error message for duplicate column names
      in <command>ANALYZE</command> (Nathan Bossart)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix mis-parsing of the last line in a
      non-newline-terminated <filename>pg_hba.conf</filename> file
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>libpq</application> to not require user's home
      directory to exist (Tom Lane)
     </para>

     <para>
      In v10, failure to find the home directory while trying to
      read <filename>~/.pgpass</filename> was treated as a hard error,
      but it should just cause that file to not be found.  Both v10 and
      previous release branches made the same mistake when
      reading <filename>~/.pg_service.conf</filename>, though this was less
      obvious since that file is not sought unless a service name is
      specified.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>libpq</application> to guard against integer
      overflow in the row count of a <structname>PGresult</structname>
      (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application>'s handling of out-of-scope cursor
      declarations with pointer or array variables (Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      Make ecpglib's Informix-compatibility mode ignore fractional digits in
      integer input strings, as expected (Gao Zengqi, Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      Sync our copy of the timezone library with IANA release tzcode2017c
      (Tom Lane)
     </para>

     <para>
      This fixes various issues; the only one likely to be user-visible
      is that the default DST rules for a POSIX-style zone name, if
      no <filename>posixrules</filename> file exists in the timezone data
      directory, now match current US law rather than what it was a dozen
      years ago.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application>
      release 2017c for DST law changes in Fiji, Namibia, Northern Cyprus,
      Sudan, Tonga, and Turks &amp; Caicos Islands, plus historical
      corrections for Alaska, Apia, Burma, Calcutta, Detroit, Ireland,
      Namibia, and Pago Pago.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-19">
  <title>Release 9.3.19</title>

  <formalpara>
  <title>Release date:</title>
  <para>2017-08-31</para>
  </formalpara>

  <para>
   This release contains a small number of fixes from 9.3.18.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.19</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.18,
    see <xref linkend="release-9-3-18"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Show foreign tables
      in <structname>information_schema</structname>.<structname>table_privileges</structname>
      view (Peter Eisentraut)
     </para>

     <para>
      All other relevant <structname>information_schema</structname> views include
      foreign tables, but this one ignored them.
     </para>

     <para>
      Since this view definition is installed by <application>initdb</application>,
      merely upgrading will not fix the problem.  If you need to fix this
      in an existing installation, you can, as a superuser, do this
      in <application>psql</application>:
<programlisting>
SET search_path TO information_schema;
CREATE OR REPLACE VIEW table_privileges AS
    SELECT CAST(u_grantor.rolname AS sql_identifier) AS grantor,
           CAST(grantee.rolname AS sql_identifier) AS grantee,
           CAST(current_database() AS sql_identifier) AS table_catalog,
           CAST(nc.nspname AS sql_identifier) AS table_schema,
           CAST(c.relname AS sql_identifier) AS table_name,
           CAST(c.prtype AS character_data) AS privilege_type,
           CAST(
             CASE WHEN
                  -- object owner always has grant options
                  pg_has_role(grantee.oid, c.relowner, 'USAGE')
                  OR c.grantable
                  THEN 'YES' ELSE 'NO' END AS yes_or_no) AS is_grantable,
           CAST(CASE WHEN c.prtype = 'SELECT' THEN 'YES' ELSE 'NO' END AS yes_or_no) AS with_hierarchy

    FROM (
            SELECT oid, relname, relnamespace, relkind, relowner, (aclexplode(coalesce(relacl, acldefault('r', relowner)))).* FROM pg_class
         ) AS c (oid, relname, relnamespace, relkind, relowner, grantor, grantee, prtype, grantable),
         pg_namespace nc,
         pg_authid u_grantor,
         (
           SELECT oid, rolname FROM pg_authid
           UNION ALL
           SELECT 0::oid, 'PUBLIC'
         ) AS grantee (oid, rolname)

    WHERE c.relnamespace = nc.oid
          AND c.relkind IN ('r', 'v', 'f')
          AND c.grantee = grantee.oid
          AND c.grantor = u_grantor.oid
          AND c.prtype IN ('INSERT', 'SELECT', 'UPDATE', 'DELETE', 'TRUNCATE', 'REFERENCES', 'TRIGGER')
          AND (pg_has_role(u_grantor.oid, 'USAGE')
               OR pg_has_role(grantee.oid, 'USAGE')
               OR grantee.rolname = 'PUBLIC');
</programlisting>
      This must be repeated in each database to be fixed,
      including <literal>template0</literal>.
     </para>
    </listitem>

    <listitem>
     <para>
      Clean up handling of a fatal exit (e.g., due to receipt
      of <systemitem>SIGTERM</systemitem>) that occurs while trying to execute
      a <command>ROLLBACK</command> of a failed transaction (Tom Lane)
     </para>

     <para>
      This situation could result in an assertion failure.  In production
      builds, the exit would still occur, but it would log an unexpected
      message about <quote>cannot drop active portal</quote>.
     </para>
    </listitem>

    <listitem>
     <para>
      Remove assertion that could trigger during a fatal exit (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Correctly identify columns that are of a range type or domain type over
      a composite type or domain type being searched for (Tom Lane)
     </para>

     <para>
      Certain <command>ALTER</command> commands that change the definition of a
      composite type or domain type are supposed to fail if there are any
      stored values of that type in the database, because they lack the
      infrastructure needed to update or check such values.  Previously,
      these checks could miss relevant values that are wrapped inside range
      types or sub-domains, possibly allowing the database to become
      inconsistent.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix crash in <application>pg_restore</application> when using parallel mode and
      using a list file to select a subset of items to restore
      (Fabr&iacute;zio de Royes Mello)
     </para>
    </listitem>

    <listitem>
     <para>
      Change <application>ecpg</application>'s parser to allow <literal>RETURNING</literal>
      clauses without attached C variables (Michael Meskes)
     </para>

     <para>
      This allows <application>ecpg</application> programs to contain SQL constructs
      that use <literal>RETURNING</literal> internally (for example, inside a CTE)
      rather than using it to define values to be returned to the client.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve selection of compiler flags for PL/Perl on Windows (Tom Lane)
     </para>

     <para>
      This fix avoids possible crashes of PL/Perl due to inconsistent
      assumptions about the width of <type>time_t</type> values.
      A side-effect that may be visible to extension developers is
      that <literal>_USE_32BIT_TIME_T</literal> is no longer defined globally
      in <productname>PostgreSQL</productname> Windows builds.  This is not expected
      to cause problems, because type <type>time_t</type> is not used
      in any <productname>PostgreSQL</productname> API definitions.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-18">
  <title>Release 9.3.18</title>

  <formalpara>
  <title>Release date:</title>
  <para>2017-08-10</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.17.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.18</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you use foreign data servers that make use of user
    passwords for authentication, see the first changelog entry below.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.16,
    see <xref linkend="release-9-3-16"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Further restrict visibility
      of <structname>pg_user_mappings</structname>.<structfield>umoptions</structfield>, to
      protect passwords stored as user mapping options
      (Noah Misch)
     </para>

     <para>
      The fix for CVE-2017-7486 was incorrect: it allowed a user
      to see the options in her own user mapping, even if she did not
      have <literal>USAGE</literal> permission on the associated foreign server.
      Such options might include a password that had been provided by the
      server owner rather than the user herself.
      Since <structname>information_schema.user_mapping_options</structname> does not
      show the options in such cases, <structname>pg_user_mappings</structname>
      should not either.
      (CVE-2017-7547)
     </para>

     <para>
      By itself, this patch will only fix the behavior in newly initdb'd
      databases.  If you wish to apply this change in an existing database,
      you will need to do the following:
     </para>

     <procedure>
      <step>
       <para>
        Restart the postmaster after adding <literal>allow_system_table_mods
        = true</literal> to <filename>postgresql.conf</filename>.  (In versions
        supporting <command>ALTER SYSTEM</command>, you can use that to make the
        configuration change, but you'll still need a restart.)
       </para>
      </step>

      <step>
       <para>
        In <emphasis>each</emphasis> database of the cluster,
        run the following commands as superuser:
<programlisting>
SET search_path = pg_catalog;
CREATE OR REPLACE VIEW pg_user_mappings AS
    SELECT
        U.oid       AS umid,
        S.oid       AS srvid,
        S.srvname   AS srvname,
        U.umuser    AS umuser,
        CASE WHEN U.umuser = 0 THEN
            'public'
        ELSE
            A.rolname
        END AS usename,
        CASE WHEN (U.umuser &lt;&gt; 0 AND A.rolname = current_user
                     AND (pg_has_role(S.srvowner, 'USAGE')
                          OR has_server_privilege(S.oid, 'USAGE')))
                    OR (U.umuser = 0 AND pg_has_role(S.srvowner, 'USAGE'))
                    OR (SELECT rolsuper FROM pg_authid WHERE rolname = current_user)
                    THEN U.umoptions
                 ELSE NULL END AS umoptions
    FROM pg_user_mapping U
         LEFT JOIN pg_authid A ON (A.oid = U.umuser) JOIN
        pg_foreign_server S ON (U.umserver = S.oid);
</programlisting>
       </para>
      </step>

      <step>
       <para>
        Do not forget to include the <literal>template0</literal>
        and <literal>template1</literal> databases, or the vulnerability will still
        exist in databases you create later.  To fix <literal>template0</literal>,
        you'll need to temporarily make it accept connections.
        In <productname>PostgreSQL</productname> 9.5 and later, you can use
<programlisting>
ALTER DATABASE template0 WITH ALLOW_CONNECTIONS true;
</programlisting>
        and then after fixing <literal>template0</literal>, undo that with
<programlisting>
ALTER DATABASE template0 WITH ALLOW_CONNECTIONS false;
</programlisting>
        In prior versions, instead use
<programlisting>
UPDATE pg_database SET datallowconn = true WHERE datname = 'template0';
UPDATE pg_database SET datallowconn = false WHERE datname = 'template0';
</programlisting>
       </para>
      </step>

      <step>
       <para>
        Finally, remove the <literal>allow_system_table_mods</literal> configuration
        setting, and again restart the postmaster.
       </para>
      </step>
     </procedure>
    </listitem>

    <listitem>
     <para>
      Disallow empty passwords in all password-based authentication methods
      (Heikki Linnakangas)
     </para>

     <para>
      <application>libpq</application> ignores empty password specifications, and does
      not transmit them to the server.  So, if a user's password has been
      set to the empty string, it's impossible to log in with that password
      via <application>psql</application> or other <application>libpq</application>-based
      clients.  An administrator might therefore believe that setting the
      password to empty is equivalent to disabling password login.
      However, with a modified or non-<application>libpq</application>-based client,
      logging in could be possible, depending on which authentication
      method is configured.  In particular the most common
      method, <literal>md5</literal>, accepted empty passwords.
      Change the server to reject empty passwords in all cases.
      (CVE-2017-7546)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix concurrent locking of tuple update chains (&Aacute;lvaro Herrera)
     </para>

     <para>
      If several sessions concurrently lock a tuple update chain with
      nonconflicting lock modes using an old snapshot, and they all
      succeed, it was possible for some of them to nonetheless fail (and
      conclude there is no live tuple version) due to a race condition.
      This had consequences such as foreign-key checks failing to see a
      tuple that definitely exists but is being updated concurrently.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix potential data corruption when freezing a tuple whose XMAX is a
      multixact with exactly one still-interesting member (Teodor Sigaev)
     </para>
    </listitem>

    <listitem>
     <para>
      On Windows, retry process creation if we fail to reserve the address
      range for our shared memory in the new process (Tom Lane, Amit
      Kapila)
     </para>

     <para>
      This is expected to fix infrequent child-process-launch failures that
      are probably due to interference from antivirus products.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix low-probability corruption of shared predicate-lock hash table
      in Windows builds (Thomas Munro, Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid logging clean closure of an SSL connection as though
      it were a connection reset (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent sending SSL session tickets to clients (Tom Lane)
     </para>

     <para>
      This fix prevents reconnection failures with ticket-aware client-side
      SSL code.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix code for setting <xref linkend="guc-tcp-keepalives-idle"/> on
      Solaris (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix statistics collector to honor inquiry messages issued just after
      a postmaster shutdown and immediate restart (Tom Lane)
     </para>

     <para>
      Statistics inquiries issued within half a second of the previous
      postmaster shutdown were effectively ignored.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that the statistics collector's receive buffer size is at
      least 100KB (Tom Lane)
     </para>

     <para>
      This reduces the risk of dropped statistics data on older platforms
      whose default receive buffer size is less than that.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible creation of an invalid WAL segment when a standby is
      promoted just after it processes an <literal>XLOG_SWITCH</literal> WAL
      record (Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <systemitem>SIGHUP</systemitem> and <systemitem>SIGUSR1</systemitem> handling in
      walsender processes (Petr Jelinek, Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix unnecessarily slow restarts of <application>walreceiver</application>
      processes due to race condition in postmaster (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix cases where an <command>INSERT</command> or <command>UPDATE</command> assigns
      to more than one element of a column that is of domain-over-array
      type (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Allow window functions to be used in sub-<literal>SELECT</literal>s that
      are within the arguments of an aggregate function (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Move autogenerated array types out of the way during
      <command>ALTER ... RENAME</command> (Vik Fearing)
     </para>

     <para>
      Previously, we would rename a conflicting autogenerated array type
      out of the way during <command>CREATE</command>; this fix extends that
      behavior to renaming operations.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that <command>ALTER USER ... SET</command> accepts all the syntax
      variants that <command>ALTER ROLE ... SET</command> does (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Properly update dependency info when changing a datatype I/O
      function's argument or return type from <type>opaque</type> to the
      correct type (Heikki Linnakangas)
     </para>

     <para>
      <command>CREATE TYPE</command> updates I/O functions declared in this
      long-obsolete style, but it forgot to record a dependency on the
      type, allowing a subsequent <command>DROP TYPE</command> to leave broken
      function definitions behind.
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce memory usage when <command>ANALYZE</command> processes
      a <type>tsvector</type> column (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix unnecessary precision loss and sloppy rounding when multiplying
      or dividing <type>money</type> values by integers or floats (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Tighten checks for whitespace in functions that parse identifiers,
      such as <function>regprocedurein()</function> (Tom Lane)
     </para>

     <para>
      Depending on the prevailing locale, these functions could
      misinterpret fragments of multibyte characters as whitespace.
     </para>
    </listitem>

    <listitem>
     <para>
      Use relevant <literal>#define</literal> symbols from Perl while
      compiling <application>PL/Perl</application> (Ashutosh Sharma, Tom Lane)
     </para>

     <para>
      This avoids portability problems, typically manifesting as
      a <quote>handshake</quote> mismatch during library load, when working with
      recent Perl versions.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>libpq</application>, reset GSS/SASL and SSPI authentication
      state properly after a failed connection attempt (Michael Paquier)
     </para>

     <para>
      Failure to do this meant that when falling back from SSL to non-SSL
      connections, a GSS/SASL failure in the SSL attempt would always cause
      the non-SSL attempt to fail.  SSPI did not fail, but it leaked memory.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>psql</application>, fix failure when <command>COPY FROM STDIN</command>
      is ended with a keyboard EOF signal and then another <command>COPY
      FROM STDIN</command> is attempted (Thomas Munro)
     </para>

     <para>
      This misbehavior was observed on BSD-derived platforms (including
      macOS), but not on most others.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> and <application>pg_restore</application> to
      emit <command>REFRESH MATERIALIZED VIEW</command> commands last (Tom Lane)
     </para>

     <para>
      This prevents errors during dump/restore when a materialized view
      refers to tables owned by a different user.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> with the <option>--clean</option> option to
      drop event triggers as expected (Tom Lane)
     </para>

     <para>
      It also now correctly assigns ownership of event triggers; before,
      they were restored as being owned by the superuser running the
      restore script.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> to not emit invalid SQL for an empty
      operator class (Daniel Gustafsson)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> output to stdout on Windows (Kuntal Ghosh)
     </para>

     <para>
      A compressed plain-text dump written to stdout would contain corrupt
      data due to failure to put the file descriptor into binary mode.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>pg_get_ruledef()</function> to print correct output for
      the <literal>ON SELECT</literal> rule of a view whose columns have been
      renamed (Tom Lane)
     </para>

     <para>
      In some corner cases, <application>pg_dump</application> relies
      on <function>pg_get_ruledef()</function> to dump views, so that this error
      could result in dump/reload failures.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of outer joins with empty constraints, such as the result
      of a <literal>NATURAL LEFT JOIN</literal> with no common columns (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of function expressions in the <literal>FROM</literal> clause in
      cases where the expression does not deparse into something that looks
      like a function call (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_basebackup</application> output to stdout on Windows
      (Haribabu Kommi)
     </para>

     <para>
      A backup written to stdout would contain corrupt data due to failure
      to put the file descriptor into binary mode.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_upgrade</application> to ensure that the ending WAL record
      does not have <xref linkend="guc-wal-level"/> = <literal>minimum</literal>
      (Bruce Momjian)
     </para>

     <para>
      This condition could prevent upgraded standby servers from
      reconnecting.
     </para>
    </listitem>

    <listitem>
     <para>
      In <filename>postgres_fdw</filename>, re-establish connections to remote
      servers after <command>ALTER SERVER</command> or <command>ALTER USER
      MAPPING</command> commands (Kyotaro Horiguchi)
     </para>

     <para>
      This ensures that option changes affecting connection parameters will
      be applied promptly.
     </para>
    </listitem>

    <listitem>
     <para>
      In <filename>postgres_fdw</filename>, allow cancellation of remote
      transaction control commands (Robert Haas, Rafia Sabih)
     </para>

     <para>
      This change allows us to quickly escape a wait for an unresponsive
      remote server in many more cases than previously.
     </para>
    </listitem>

    <listitem>
     <para>
      Always use <option>-fPIC</option>, not <option>-fpic</option>, when building
      shared libraries with gcc (Tom Lane)
     </para>

     <para>
      This supports larger extension libraries on platforms where it makes
      a difference.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix unescaped-braces issue in our build scripts for Microsoft MSVC,
      to avoid a warning or error from recent Perl versions (Andrew
      Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      In MSVC builds, handle the case where the <application>OpenSSL</application>
      library is not within a <filename>VC</filename> subdirectory (Andrew Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      In MSVC builds, add proper include path for <application>libxml2</application>
      header files (Andrew Dunstan)
     </para>

     <para>
      This fixes a former need to move things around in standard Windows
      installations of <application>libxml2</application>.
     </para>
    </listitem>

    <listitem>
     <para>
      In MSVC builds, recognize a Tcl library that is
      named <filename>tcl86.lib</filename> (Noah Misch)
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-17">
  <title>Release 9.3.17</title>

  <formalpara>
  <title>Release date:</title>
  <para>2017-05-11</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.16.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.17</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you use foreign data servers that make use of user
    passwords for authentication, see the first changelog entry below.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.16,
    see <xref linkend="release-9-3-16"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Restrict visibility
      of <structname>pg_user_mappings</structname>.<structfield>umoptions</structfield>, to
      protect passwords stored as user mapping options
      (Michael Paquier, Feike Steenbergen)
     </para>

     <para>
      The previous coding allowed the owner of a foreign server object,
      or anyone he has granted server <literal>USAGE</literal> permission to,
      to see the options for all user mappings associated with that server.
      This might well include passwords for other users.
      Adjust the view definition to match the behavior of
      <structname>information_schema.user_mapping_options</structname>, namely that
      these options are visible to the user being mapped, or if the mapping
      is for <literal>PUBLIC</literal> and the current user is the server
      owner, or if the current user is a superuser.
      (CVE-2017-7486)
     </para>

     <para>
      By itself, this patch will only fix the behavior in newly initdb'd
      databases.  If you wish to apply this change in an existing database,
      follow the corrected procedure shown in the changelog entry for
      CVE-2017-7547, in <xref linkend="release-9-3-18"/>.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent exposure of statistical information via leaky operators
      (Peter Eisentraut)
     </para>

     <para>
      Some selectivity estimation functions in the planner will apply
      user-defined operators to values obtained
      from <structname>pg_statistic</structname>, such as most common values and
      histogram entries.  This occurs before table permissions are checked,
      so a nefarious user could exploit the behavior to obtain these values
      for table columns he does not have permission to read.  To fix,
      fall back to a default estimate if the operator's implementation
      function is not certified leak-proof and the calling user does not have
      permission to read the table column whose statistics are needed.
      At least one of these criteria is satisfied in most cases in practice.
      (CVE-2017-7484)
     </para>
    </listitem>

    <listitem>
     <para>
      Restore <application>libpq</application>'s recognition of
      the <envar>PGREQUIRESSL</envar> environment variable (Daniel Gustafsson)
     </para>

     <para>
      Processing of this environment variable was unintentionally dropped
      in <productname>PostgreSQL</productname> 9.3, but its documentation remained.
      This creates a security hazard, since users might be relying on the
      environment variable to force SSL-encrypted connections, but that
      would no longer be guaranteed.  Restore handling of the variable,
      but give it lower priority than <envar>PGSSLMODE</envar>, to avoid
      breaking configurations that work correctly with post-9.3 code.
      (CVE-2017-7485)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible corruption of <quote>init forks</quote> of unlogged indexes
      (Robert Haas, Michael Paquier)
     </para>

     <para>
      This could result in an unlogged index being set to an invalid state
      after a crash and restart.  Such a problem would persist until the
      index was dropped and rebuilt.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect reconstruction of <structname>pg_subtrans</structname> entries
      when a standby server replays a prepared but uncommitted two-phase
      transaction (Tom Lane)
     </para>

     <para>
      In most cases this turned out to have no visible ill effects, but in
      corner cases it could result in circular references
      in <structname>pg_subtrans</structname>, potentially causing infinite loops
      in queries that examine rows modified by the two-phase transaction.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure parsing of queries in extension scripts sees the results of
      immediately-preceding DDL (Julien Rouhaud, Tom Lane)
     </para>

     <para>
      Due to lack of a cache flush step between commands in an extension
      script file, non-utility queries might not see the effects of an
      immediately preceding catalog change, such as <command>ALTER TABLE
      ... RENAME</command>.
     </para>
    </listitem>

    <listitem>
     <para>
      Skip tablespace privilege checks when <command>ALTER TABLE ... ALTER
      COLUMN TYPE</command> rebuilds an existing index (Noah Misch)
     </para>

     <para>
      The command failed if the calling user did not currently have
      <literal>CREATE</literal> privilege for the tablespace containing the index.
      That behavior seems unhelpful, so skip the check, allowing the
      index to be rebuilt where it is.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>ALTER TABLE ... VALIDATE CONSTRAINT</command> to not recurse
      to child tables when the constraint is marked <literal>NO INHERIT</literal>
      (Amit Langote)
     </para>

     <para>
      This fix prevents unwanted <quote>constraint does not exist</quote> failures
      when no matching constraint is present in the child tables.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>VACUUM</command> to account properly for pages that could not
      be scanned due to conflicting page pins (Andrew Gierth)
     </para>

     <para>
      This tended to lead to underestimation of the number of tuples in
      the table.  In the worst case of a small heavily-contended
      table, <command>VACUUM</command> could incorrectly report that the table
      contained no tuples, leading to very bad planning choices.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that bulk-tuple-transfer loops within a hash join are
      interruptible by query cancel requests (Tom Lane, Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>cursor_to_xml()</function> to produce valid output
      with <replaceable>tableforest</replaceable> = false
      (Thomas Munro, Peter Eisentraut)
     </para>

     <para>
      Previously it failed to produce a wrapping <literal>&lt;table&gt;</literal>
      element.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve performance of <structname>pg_timezone_names</structname> view
      (Tom Lane, David Rowley)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix sloppy handling of corner-case errors from <function>lseek()</function>
      and <function>close()</function> (Tom Lane)
     </para>

     <para>
      Neither of these system calls are likely to fail in typical situations,
      but if they did, <filename>fd.c</filename> could get quite confused.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect check for whether postmaster is running as a Windows
      service (Michael Paquier)
     </para>

     <para>
      This could result in attempting to write to the event log when that
      isn't accessible, so that no logging happens at all.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application> to support <command>COMMIT PREPARED</command>
      and <command>ROLLBACK PREPARED</command> (Masahiko Sawada)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix a double-free error when processing dollar-quoted string literals
      in <application>ecpg</application> (Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</application>, fix incorrect schema and owner marking for
      comments and security labels of some types of database objects
      (Giuseppe Broccolo, Tom Lane)
     </para>

     <para>
      In simple cases this caused no ill effects; but for example, a
      schema-selective restore might omit comments it should include, because
      they were not marked as belonging to the schema of their associated
      object.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid emitting an invalid list file in <literal>pg_restore -l</literal>
      when SQL object names contain newlines (Tom Lane)
     </para>

     <para>
      Replace newlines by spaces, which is sufficient to make the output
      valid for <literal>pg_restore -L</literal>'s purposes.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_upgrade</application> to transfer comments and security labels
      attached to <quote>large objects</quote> (blobs) (Stephen Frost)
     </para>

     <para>
      Previously, blobs were correctly transferred to the new database, but
      any comments or security labels attached to them were lost.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve error handling
      in <filename>contrib/adminpack</filename>'s <function>pg_file_write()</function>
      function (Noah Misch)
     </para>

     <para>
      Notably, it failed to detect errors reported
      by <function>fclose()</function>.
     </para>
    </listitem>

    <listitem>
     <para>
      In <filename>contrib/dblink</filename>, avoid leaking the previous unnamed
      connection when establishing a new unnamed connection (Joe Conway)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <filename>contrib/pg_trgm</filename>'s extraction of trigrams from regular
      expressions (Tom Lane)
     </para>

     <para>
      In some cases it would produce a broken data structure that could never
      match anything, leading to GIN or GiST indexscans that use a trigram
      index not finding any matches to the regular expression.
     </para>
    </listitem>

    <listitem>
     <para>
      In <filename>contrib/postgres_fdw</filename>,
      transmit query cancellation requests to the remote server
      (Michael Paquier, Etsuro Fujita)
     </para>

     <para>
      Previously, a local query cancellation request did not cause an
      already-sent remote query to terminate early.  This is a back-patch
      of work originally done for 9.6.
     </para>
    </listitem>

    <listitem>
     <para>
      Support OpenSSL 1.1.0 (Heikki Linnakangas, Andreas Karlsson, Tom Lane)
     </para>

     <para>
      This is a back-patch of work previously done in newer branches;
      it's needed since many platforms are adopting newer OpenSSL versions.
     </para>
    </listitem>

    <listitem>
     <para>
      Support Tcl 8.6 in MSVC builds (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Sync our copy of the timezone library with IANA release tzcode2017b
      (Tom Lane)
     </para>

     <para>
      This fixes a bug affecting some DST transitions in January 2038.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2017b
      for DST law changes in Chile, Haiti, and Mongolia, plus historical
      corrections for Ecuador, Kazakhstan, Liberia, and Spain.
      Switch to numeric abbreviations for numerous time zones in South
      America, the Pacific and Indian oceans, and some Asian and Middle
      Eastern countries.
     </para>

     <para>
      The IANA time zone database previously provided textual abbreviations
      for all time zones, sometimes making up abbreviations that have little
      or no currency among the local population.  They are in process of
      reversing that policy in favor of using numeric UTC offsets in zones
      where there is no evidence of real-world use of an English
      abbreviation.  At least for the time being, <productname>PostgreSQL</productname>
      will continue to accept such removed abbreviations for timestamp input.
      But they will not be shown in the <structname>pg_timezone_names</structname>
      view nor used for output.
     </para>
    </listitem>

    <listitem>
     <para>
      Use correct daylight-savings rules for POSIX-style time zone names
      in MSVC builds (David Rowley)
     </para>

     <para>
      The Microsoft MSVC build scripts neglected to install
      the <filename>posixrules</filename> file in the timezone directory tree.
      This resulted in the timezone code falling back to its built-in
      rule about what DST behavior to assume for a POSIX-style time zone
      name.  For historical reasons that still corresponds to the DST rules
      the USA was using before 2007 (i.e., change on first Sunday in April
      and last Sunday in October).  With this fix, a POSIX-style zone name
      will use the current and historical DST transition dates of
      the <literal>US/Eastern</literal> zone.  If you don't want that, remove
      the <filename>posixrules</filename> file, or replace it with a copy of some
      other zone file (see <xref linkend="datatype-timezones"/>).  Note that
      due to caching, you may need to restart the server to get such changes
      to take effect.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-16">
  <title>Release 9.3.16</title>

  <formalpara>
  <title>Release date:</title>
  <para>2017-02-09</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.15.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.16</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if your installation has been affected by the bug described in
    the first changelog entry below, then after updating you may need
    to take action to repair corrupted indexes.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.15,
    see <xref linkend="release-9-3-15"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix a race condition that could cause indexes built
      with <command>CREATE INDEX CONCURRENTLY</command> to be corrupt
      (Pavan Deolasee, Tom Lane)
     </para>

     <para>
      If <command>CREATE INDEX CONCURRENTLY</command> was used to build an index
      that depends on a column not previously indexed, then rows
      updated by transactions that ran concurrently with
      the <command>CREATE INDEX</command> command could have received incorrect
      index entries.  If you suspect this may have happened, the most
      reliable solution is to rebuild affected indexes after installing
      this update.
     </para>
    </listitem>

    <listitem>
     <para>
      Unconditionally WAL-log creation of the <quote>init fork</quote> for an
      unlogged table (Michael Paquier)
     </para>

     <para>
      Previously, this was skipped when <xref linkend="guc-wal-level"/>
      = <literal>minimal</literal>, but actually it's necessary even in that case
      to ensure that the unlogged table is properly reset to empty after a
      crash.
     </para>
    </listitem>

    <listitem>
     <para>
      If the stats collector dies during hot standby, restart it (Takayuki
      Tsunakawa)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that hot standby feedback works correctly when it's enabled at
      standby server start (Ants Aasma, Craig Ringer)
     </para>
    </listitem>

    <listitem>
     <para>
      Check for interrupts while hot standby is waiting for a conflicting
      query (Simon Riggs)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid constantly respawning the autovacuum launcher in a corner case
      (Amit Khandekar)
     </para>

     <para>
      This fix avoids problems when autovacuum is nominally off and there
      are some tables that require freezing, but all such tables are
      already being processed by autovacuum workers.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix check for when an extension member object can be dropped (Tom Lane)
     </para>

     <para>
      Extension upgrade scripts should be able to drop member objects,
      but this was disallowed for serial-column sequences, and possibly
      other cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Make sure <command>ALTER TABLE</command> preserves index tablespace
      assignments when rebuilding indexes (Tom Lane, Michael Paquier)
     </para>

     <para>
      Previously, non-default settings
      of <xref linkend="guc-default-tablespace"/> could result in broken
      indexes.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent dropping a foreign-key constraint if there are pending
      trigger events for the referenced relation (Tom Lane)
     </para>

     <para>
      This avoids <quote>could not find trigger <replaceable>NNN</replaceable></quote>
      or <quote>relation <replaceable>NNN</replaceable> has no triggers</quote> errors.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix processing of OID column when a table with OIDs is associated to
      a parent with OIDs via <command>ALTER TABLE ... INHERIT</command> (Amit
      Langote)
     </para>

     <para>
      The OID column should be treated the same as regular user columns in
      this case, but it wasn't, leading to odd behavior in later
      inheritance changes.
     </para>
    </listitem>

    <listitem>
     <para>
      Report correct object identity during <command>ALTER TEXT SEARCH
      CONFIGURATION</command> (Artur Zakirov)
     </para>

     <para>
      The wrong catalog OID was reported to extensions such as logical
      decoding.
     </para>
    </listitem>

    <listitem>
     <para>
      Check for serializability conflicts before reporting
      constraint-violation failures (Thomas Munro)
     </para>

     <para>
      When using serializable transaction isolation, it is desirable
      that any error due to concurrent transactions should manifest
      as a serialization failure, thereby cueing the application that
      a retry might succeed.  Unfortunately, this does not reliably
      happen for duplicate-key failures caused by concurrent insertions.
      This change ensures that such an error will be reported as a
      serialization error if the application explicitly checked for
      the presence of a conflicting key (and did not find it) earlier
      in the transaction.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent multicolumn expansion of <replaceable>foo</replaceable><literal>.*</literal> in
      an <command>UPDATE</command> source expression (Tom Lane)
     </para>

     <para>
      This led to <quote>UPDATE target count mismatch --- internal
      error</quote>.  Now the syntax is understood as a whole-row variable,
      as it would be in other contexts.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that column typmods are determined accurately for
      multi-row <literal>VALUES</literal> constructs (Tom Lane)
     </para>

     <para>
      This fixes problems occurring when the first value in a column has a
      determinable typmod (e.g., length for a <type>varchar</type> value) but
      later values don't share the same limit.
     </para>
    </listitem>

    <listitem>
     <para>
      Throw error for an unfinished Unicode surrogate pair at the end of a
      Unicode string (Tom Lane)
     </para>

     <para>
      Normally, a Unicode surrogate leading character must be followed by a
      Unicode surrogate trailing character, but the check for this was
      missed if the leading character was the last character in a Unicode
      string literal (<literal>U&amp;'...'</literal>) or Unicode identifier
      (<literal>U&amp;"..."</literal>).
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that a purely negative text search query, such
      as <literal>!foo</literal>, matches empty <type>tsvector</type>s (Tom Dunstan)
     </para>

     <para>
      Such matches were found by GIN index searches, but not by sequential
      scans or GiST index searches.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent crash when <function>ts_rewrite()</function> replaces a non-top-level
      subtree with an empty query (Artur Zakirov)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix performance problems in <function>ts_rewrite()</function> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>ts_rewrite()</function>'s handling of nested NOT operators
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>array_fill()</function> to handle empty arrays properly (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix one-byte buffer overrun in <function>quote_literal_cstr()</function>
      (Heikki Linnakangas)
     </para>

     <para>
      The overrun occurred only if the input consisted entirely of single
      quotes and/or backslashes.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent multiple calls of <function>pg_start_backup()</function>
      and <function>pg_stop_backup()</function> from running concurrently (Michael
      Paquier)
     </para>

     <para>
      This avoids an assertion failure, and possibly worse things, if
      someone tries to run these functions in parallel.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid discarding <type>interval</type>-to-<type>interval</type> casts
      that aren't really no-ops (Tom Lane)
     </para>

     <para>
      In some cases, a cast that should result in zeroing out
      low-order <type>interval</type> fields was mistakenly deemed to be a
      no-op and discarded.  An example is that casting from <type>INTERVAL
      MONTH</type> to <type>INTERVAL YEAR</type> failed to clear the months field.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that cached plans are invalidated by changes in foreign-table
      options (Amit Langote, Etsuro Fujita, Ashutosh Bapat)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> to dump user-defined casts and transforms
      that use built-in functions (Stephen Frost)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible <application>pg_basebackup</application> failure on standby
      server when including WAL files (Amit Kapila, Robert Haas)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that the Python exception objects we create for PL/Python are
      properly reference-counted (Rafa de la Torre, Tom Lane)
     </para>

     <para>
      This avoids failures if the objects are used after a Python garbage
      collection cycle has occurred.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix PL/Tcl to support triggers on tables that have <literal>.tupno</literal>
      as a column name (Tom Lane)
     </para>

     <para>
      This matches the (previously undocumented) behavior of
      PL/Tcl's <command>spi_exec</command> and <command>spi_execp</command> commands,
      namely that a magic <literal>.tupno</literal> column is inserted only if
      there isn't a real column named that.
     </para>
    </listitem>

    <listitem>
     <para>
      Allow DOS-style line endings in <filename>~/.pgpass</filename> files,
      even on Unix (Vik Fearing)
     </para>

     <para>
      This change simplifies use of the same password file across Unix and
      Windows machines.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix one-byte buffer overrun if <application>ecpg</application> is given a file
      name that ends with a dot (Takayuki Tsunakawa)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</application>'s tab completion for <command>ALTER DEFAULT
      PRIVILEGES</command> (Gilles Darold, Stephen Frost)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>psql</application>, treat an empty or all-blank setting of
      the <envar>PAGER</envar> environment variable as meaning <quote>no
      pager</quote> (Tom Lane)
     </para>

     <para>
      Previously, such a setting caused output intended for the pager to
      vanish entirely.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve <filename>contrib/dblink</filename>'s reporting of
      low-level <application>libpq</application> errors, such as out-of-memory
      (Joe Conway)
     </para>
    </listitem>

    <listitem>
     <para>
      Teach <filename>contrib/dblink</filename> to ignore irrelevant server options
      when it uses a <filename>contrib/postgres_fdw</filename> foreign server as
      the source of connection options (Corey Huinker)
     </para>

     <para>
      Previously, if the foreign server object had options that were not
      also <application>libpq</application> connection options, an error occurred.
     </para>
    </listitem>

    <listitem>
     <para>
      On Windows, ensure that environment variable changes are propagated
      to DLLs built with debug options (Christian Ullrich)
     </para>
    </listitem>

    <listitem>
     <para>
      Sync our copy of the timezone library with IANA release tzcode2016j
      (Tom Lane)
     </para>

     <para>
      This fixes various issues, most notably that timezone data
      installation failed if the target directory didn't support hard
      links.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2016j
      for DST law changes in northern Cyprus (adding a new zone
      Asia/Famagusta), Russia (adding a new zone Europe/Saratov), Tonga,
      and Antarctica/Casey.
      Historical corrections for Italy, Kazakhstan, Malta, and Palestine.
      Switch to preferring numeric zone abbreviations for Tonga.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-15">
  <title>Release 9.3.15</title>

  <formalpara>
  <title>Release date:</title>
  <para>2016-10-27</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.14.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.15</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if your installation has been affected by the bug described in
    the first changelog entry below, then after updating you may need
    to take action to repair corrupted free space maps.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.9,
    see <xref linkend="release-9-3-9"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix WAL-logging of truncation of relation free space maps and
      visibility maps (Pavan Deolasee, Heikki Linnakangas)
     </para>

     <para>
      It was possible for these files to not be correctly restored during
      crash recovery, or to be written incorrectly on a standby server.
      Bogus entries in a free space map could lead to attempts to access
      pages that have been truncated away from the relation itself, typically
      producing errors like <quote>could not read block <replaceable>XXX</replaceable>:
      read only 0 of 8192 bytes</quote>.  Checksum failures in the
      visibility map are also possible, if checksumming is enabled.
     </para>

     <para>
      Procedures for determining whether there is a problem and repairing it
      if so are discussed at
      <ulink url="https://wiki.postgresql.org/wiki/Free_Space_Map_Problems"></ulink>.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>SELECT FOR UPDATE/SHARE</command> to correctly lock tuples that
      have been updated by a subsequently-aborted transaction
      (&Aacute;lvaro Herrera)
     </para>

     <para>
      In 9.5 and later, the <command>SELECT</command> would sometimes fail to
      return such tuples at all.  A failure has not been proven to occur in
      earlier releases, but might be possible with concurrent updates.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix EvalPlanQual rechecks involving CTE scans (Tom Lane)
     </para>

     <para>
      The recheck would always see the CTE as returning no rows, typically
      leading to failure to update rows that were recently updated.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix improper repetition of previous results from hashed aggregation in
      a subquery (Andrew Gierth)
     </para>

     <para>
      The test to see if we can reuse a previously-computed hash table of
      the aggregate state values neglected the possibility of an outer query
      reference appearing in an aggregate argument expression.  A change in
      the value of such a reference should lead to recalculating the hash
      table, but did not.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>EXPLAIN</command> to emit valid XML when
      <xref linkend="guc-track-io-timing"/> is on (Markus Winand)
     </para>

     <para>
      Previously the XML output-format option produced syntactically invalid
      tags such as <literal>&lt;I/O-Read-Time&gt;</literal>.  That is now
      rendered as <literal>&lt;I-O-Read-Time&gt;</literal>.
     </para>
    </listitem>

    <listitem>
     <para>
      Suppress printing of zeroes for unmeasured times
      in <command>EXPLAIN</command> (Maksim Milyutin)
     </para>

     <para>
      Certain option combinations resulted in printing zero values for times
      that actually aren't ever measured in that combination.  Our general
      policy in <command>EXPLAIN</command> is not to print such fields at all, so
      do that consistently in all cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix timeout length when <command>VACUUM</command> is waiting for exclusive
      table lock so that it can truncate the table (Simon Riggs)
     </para>

     <para>
      The timeout was meant to be 50 milliseconds, but it was actually only
      50 microseconds, causing <command>VACUUM</command> to give up on truncation
      much more easily than intended.  Set it to the intended value.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix bugs in merging inherited <literal>CHECK</literal> constraints while
      creating or altering a table (Tom Lane, Amit Langote)
     </para>

     <para>
      Allow identical <literal>CHECK</literal> constraints to be added to a parent
      and child table in either order.  Prevent merging of a valid
      constraint from the parent table with a <literal>NOT VALID</literal>
      constraint on the child.  Likewise, prevent merging of a <literal>NO
      INHERIT</literal> child constraint with an inherited constraint.
     </para>
    </listitem>

    <listitem>
     <para>
      Remove artificial restrictions on the values accepted
      by <function>numeric_in()</function> and <function>numeric_recv()</function>
      (Tom Lane)
     </para>

     <para>
      We allow numeric values up to the limit of the storage format (more
      than <literal>1e100000</literal>), so it seems fairly pointless
      that <function>numeric_in()</function> rejected scientific-notation exponents
      above 1000.  Likewise, it was silly for <function>numeric_recv()</function> to
      reject more than 1000 digits in an input value.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid very-low-probability data corruption due to testing tuple
      visibility without holding buffer lock (Thomas Munro, Peter Geoghegan,
      Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix file descriptor leakage when truncating a temporary relation of
      more than 1GB (Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Disallow starting a standalone backend with <literal>standby_mode</literal>
      turned on (Michael Paquier)
     </para>

     <para>
      This can't do anything useful, since there will be no WAL receiver
      process to fetch more WAL data; and it could result in misbehavior
      in code that wasn't designed with this situation in mind.
     </para>
    </listitem>

    <listitem>
     <para>
      Don't try to share SSL contexts across multiple connections
      in <application>libpq</application> (Heikki Linnakangas)
     </para>

     <para>
      This led to assorted corner-case bugs, particularly when trying to use
      different SSL parameters for different connections.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid corner-case memory leak in <application>libpq</application> (Tom Lane)
     </para>

     <para>
      The reported problem involved leaking an error report
      during <function>PQreset()</function>, but there might be related cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>ecpg</application>'s <option>--help</option> and <option>--version</option>
      options work consistently with our other executables (Haribabu Kommi)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</application>, never dump range constructor functions
      (Tom Lane)
     </para>

     <para>
      This oversight led to <application>pg_upgrade</application> failures with
      extensions containing range types, due to duplicate creation of the
      constructor functions.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_xlogdump</application>, retry opening new WAL segments when
      using <option>--follow</option> option (Magnus Hagander)
     </para>

     <para>
      This allows for a possible delay in the server's creation of the next
      segment.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_xlogdump</application> to cope with a WAL file that begins
      with a continuation record spanning more than one page (Pavan
      Deolasee)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <filename>contrib/intarray/bench/bench.pl</filename> to print the results
      of the <command>EXPLAIN</command> it does when given the <option>-e</option> option
      (Daniel Gustafsson)
     </para>
    </listitem>

    <listitem>
     <para>
      Update Windows time zone mapping to recognize some time zone names
      added in recent Windows versions (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent failure of obsolete dynamic time zone abbreviations (Tom Lane)
     </para>

     <para>
      If a dynamic time zone abbreviation does not match any entry in the
      referenced time zone, treat it as equivalent to the time zone name.
      This avoids unexpected failures when IANA removes abbreviations from
      their time zone database, as they did in <application>tzdata</application>
      release 2016f and seem likely to do again in the future.  The
      consequences were not limited to not recognizing the individual
      abbreviation; any mismatch caused
      the <structname>pg_timezone_abbrevs</structname> view to fail altogether.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2016h
      for DST law changes in Palestine and Turkey, plus historical
      corrections for Turkey and some regions of Russia.
      Switch to numeric abbreviations for some time zones in Antarctica,
      the former Soviet Union, and Sri Lanka.
     </para>

     <para>
      The IANA time zone database previously provided textual abbreviations
      for all time zones, sometimes making up abbreviations that have little
      or no currency among the local population.  They are in process of
      reversing that policy in favor of using numeric UTC offsets in zones
      where there is no evidence of real-world use of an English
      abbreviation.  At least for the time being, <productname>PostgreSQL</productname>
      will continue to accept such removed abbreviations for timestamp input.
      But they will not be shown in the <structname>pg_timezone_names</structname>
      view nor used for output.
     </para>

     <para>
      In this update, <literal>AMT</literal> is no longer shown as being in use to
      mean Armenia Time.  Therefore, we have changed the <literal>Default</literal>
      abbreviation set to interpret it as Amazon Time, thus UTC-4 not UTC+4.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-14">
  <title>Release 9.3.14</title>

  <formalpara>
  <title>Release date:</title>
  <para>2016-08-11</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.13.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.14</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.9,
    see <xref linkend="release-9-3-9"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix possible mis-evaluation of
      nested <literal>CASE</literal>-<literal>WHEN</literal> expressions (Heikki
      Linnakangas, Michael Paquier, Tom Lane)
     </para>

     <para>
      A <literal>CASE</literal> expression appearing within the test value
      subexpression of another <literal>CASE</literal> could become confused about
      whether its own test value was null or not.  Also, inlining of a SQL
      function implementing the equality operator used by
      a <literal>CASE</literal> expression could result in passing the wrong test
      value to functions called within a <literal>CASE</literal> expression in the
      SQL function's body.  If the test values were of different data
      types, a crash might result; moreover such situations could be abused
      to allow disclosure of portions of server memory.  (CVE-2016-5423)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix client programs' handling of special characters in database and
      role names (Noah Misch, Nathan Bossart, Michael Paquier)
     </para>

     <para>
      Numerous places in <application>vacuumdb</application> and other client programs
      could become confused by database and role names containing double
      quotes or backslashes.  Tighten up quoting rules to make that safe.
      Also, ensure that when a conninfo string is used as a database name
      parameter to these programs, it is correctly treated as such throughout.
     </para>

     <para>
      Fix handling of paired double quotes
      in <application>psql</application>'s <command>\connect</command>
      and <command>\password</command> commands to match the documentation.
     </para>

     <para>
      Introduce a new <option>-reuse-previous</option> option
      in <application>psql</application>'s <command>\connect</command> command to allow
      explicit control of whether to re-use connection parameters from a
      previous connection.  (Without this, the choice is based on whether
      the database name looks like a conninfo string, as before.)  This
      allows secure handling of database names containing special
      characters in <application>pg_dumpall</application> scripts.
     </para>

     <para>
      <application>pg_dumpall</application> now refuses to deal with database and role
      names containing carriage returns or newlines, as it seems impractical
      to quote those characters safely on Windows.  In future we may reject
      such names on the server side, but that step has not been taken yet.
     </para>

     <para>
      These are considered security fixes because crafted object names
      containing special characters could have been used to execute
      commands with superuser privileges the next time a superuser
      executes <application>pg_dumpall</application> or other routine maintenance
      operations.  (CVE-2016-5424)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix corner-case misbehaviors for <literal>IS NULL</literal>/<literal>IS NOT
      NULL</literal> applied to nested composite values (Andrew Gierth, Tom Lane)
     </para>

     <para>
      The SQL standard specifies that <literal>IS NULL</literal> should return
      TRUE for a row of all null values (thus <literal>ROW(NULL,NULL) IS
      NULL</literal> yields TRUE), but this is not meant to apply recursively
      (thus <literal>ROW(NULL, ROW(NULL,NULL)) IS NULL</literal> yields FALSE).
      The core executor got this right, but certain planner optimizations
      treated the test as recursive (thus producing TRUE in both cases),
      and <filename>contrib/postgres_fdw</filename> could produce remote queries
      that misbehaved similarly.
     </para>
    </listitem>

    <listitem>
     <para>
      Make the <type>inet</type> and <type>cidr</type> data types properly reject
      IPv6 addresses with too many colon-separated fields (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent crash in <function>close_ps()</function>
      (the <type>point</type> <literal>##</literal> <type>lseg</type> operator)
      for NaN input coordinates (Tom Lane)
     </para>

     <para>
      Make it return NULL instead of crashing.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid possible crash in <function>pg_get_expr()</function> when inconsistent
      values are passed to it (Michael Paquier, Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix several one-byte buffer over-reads in <function>to_number()</function>
      (Peter Eisentraut)
     </para>

     <para>
      In several cases the <function>to_number()</function> function would read one
      more character than it should from the input string.  There is a
      small chance of a crash, if the input happens to be adjacent to the
      end of memory.
     </para>
    </listitem>

    <listitem>
     <para>
      Do not run the planner on the query contained in <literal>CREATE
      MATERIALIZED VIEW</literal> or <literal>CREATE TABLE AS</literal>
      when <literal>WITH NO DATA</literal> is specified (Michael Paquier,
      Tom Lane)
     </para>

     <para>
      This avoids some unnecessary failure conditions, for example if a
      stable function invoked by the materialized view depends on a table
      that doesn't exist yet.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid unsafe intermediate state during expensive paths
      through <function>heap_update()</function> (Masahiko Sawada, Andres Freund)
     </para>

     <para>
      Previously, these cases locked the target tuple (by setting its XMAX)
      but did not WAL-log that action, thus risking data integrity problems
      if the page were spilled to disk and then a database crash occurred
      before the tuple update could be completed.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix hint bit update during WAL replay of row locking operations
      (Andres Freund)
     </para>

     <para>
      The only known consequence of this problem is that row locks held by
      a prepared, but uncommitted, transaction might fail to be enforced
      after a crash and restart.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid unnecessary <quote>could not serialize access</quote> errors when
      acquiring <literal>FOR KEY SHARE</literal> row locks in serializable mode
      (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid crash in <literal>postgres -C</literal> when the specified variable
      has a null string value (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that backends see up-to-date statistics for shared catalogs
      (Tom Lane)
     </para>

     <para>
      The statistics collector failed to update the statistics file for
      shared catalogs after a request from a regular backend.  This problem
      was partially masked because the autovacuum launcher regularly makes
      requests that did cause such updates; however, it became obvious with
      autovacuum disabled.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid redundant writes of the statistics files when multiple
      backends request updates close together (Tom Lane, Tomas Vondra)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid consuming a transaction ID during <command>VACUUM</command>
      (Alexander Korotkov)
     </para>

     <para>
      Some cases in <command>VACUUM</command> unnecessarily caused an XID to be
      assigned to the current transaction.  Normally this is negligible,
      but if one is up against the XID wraparound limit, consuming more
      XIDs during anti-wraparound vacuums is a very bad thing.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid canceling hot-standby queries during <command>VACUUM FREEZE</command>
      (Simon Riggs, &Aacute;lvaro Herrera)
     </para>

     <para>
      <command>VACUUM FREEZE</command> on an otherwise-idle master server could
      result in unnecessary cancellations of queries on its standby
      servers.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent possible failure when vacuuming multixact IDs in an
      installation that has been pg_upgrade'd from pre-9.3 (Andrew Gierth,
      &Aacute;lvaro Herrera)
     </para>

     <para>
      The usual symptom of this bug is errors
      like <quote>MultiXactId <replaceable>NNN</replaceable> has not been created
      yet -- apparent wraparound</quote>.
     </para>
    </listitem>

    <listitem>
     <para>
      When a manual <command>ANALYZE</command> specifies a column list, don't
      reset the table's <literal>changes_since_analyze</literal> counter
      (Tom Lane)
     </para>

     <para>
      If we're only analyzing some columns, we should not prevent routine
      auto-analyze from happening for the other columns.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>ANALYZE</command>'s overestimation of <literal>n_distinct</literal>
      for a unique or nearly-unique column with many null entries (Tom
      Lane)
     </para>

     <para>
      The nulls could get counted as though they were themselves distinct
      values, leading to serious planner misestimates in some types of
      queries.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent autovacuum from starting multiple workers for the same shared
      catalog (&Aacute;lvaro Herrera)
     </para>

     <para>
      Normally this isn't much of a problem because the vacuum doesn't take
      long anyway; but in the case of a severely bloated catalog, it could
      result in all but one worker uselessly waiting instead of doing
      useful work on other tables.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent infinite loop in GiST index build for geometric columns
      containing NaN component values (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <filename>contrib/btree_gin</filename> to handle the smallest
      possible <type>bigint</type> value correctly (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Teach libpq to correctly decode server version from future servers
      (Peter Eisentraut)
     </para>

     <para>
      It's planned to switch to two-part instead of three-part server
      version numbers for releases after 9.6.  Make sure
      that <function>PQserverVersion()</function> returns the correct value for
      such cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application>'s code for <literal>unsigned long long</literal>
      array elements (Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</application> with both <option>-c</option> and <option>-C</option>
      options, avoid emitting an unwanted <literal>CREATE SCHEMA public</literal>
      command (David Johnston, Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Improve handling of <systemitem>SIGTERM</systemitem>/control-C in
      parallel <application>pg_dump</application> and <application>pg_restore</application> (Tom
      Lane)
     </para>

     <para>
      Make sure that the worker processes will exit promptly, and also arrange
      to send query-cancel requests to the connected backends, in case they
      are doing something long-running such as a <command>CREATE INDEX</command>.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix error reporting in parallel <application>pg_dump</application>
      and <application>pg_restore</application> (Tom Lane)
     </para>

     <para>
      Previously, errors reported by <application>pg_dump</application>
      or <application>pg_restore</application> worker processes might never make it to
      the user's console, because the messages went through the master
      process, and there were various deadlock scenarios that would prevent
      the master process from passing on the messages.  Instead, just print
      everything to <literal>stderr</literal>.  In some cases this will result in
      duplicate messages (for instance, if all the workers report a server
      shutdown), but that seems better than no message.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that parallel <application>pg_dump</application>
      or <application>pg_restore</application> on Windows will shut down properly
      after an error (Kyotaro Horiguchi)
     </para>

     <para>
      Previously, it would report the error, but then just sit until
      manually stopped by the user.
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_dump</application> behave better when built without zlib
      support (Kyotaro Horiguchi)
     </para>

     <para>
      It didn't work right for parallel dumps, and emitted some rather
      pointless warnings in other cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_basebackup</application> accept <literal>-Z 0</literal> as
      specifying no compression (Fujii Masao)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix makefiles' rule for building AIX shared libraries to be safe for
      parallel make (Noah Misch)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix TAP tests and MSVC scripts to work when build directory's path
      name contains spaces (Michael Paquier, Kyotaro Horiguchi)
     </para>
    </listitem>

    <listitem>
     <para>
      Be more predictable about reporting <quote>statement timeout</quote>
      versus <quote>lock timeout</quote> (Tom Lane)
     </para>

     <para>
      On heavily loaded machines, the regression tests sometimes failed due
      to reporting <quote>lock timeout</quote> even though the statement timeout
      should have occurred first.
     </para>
    </listitem>

    <listitem>
     <para>
      Make regression tests safe for Danish and Welsh locales (Jeff Janes,
      Tom Lane)
     </para>

     <para>
      Change some test data that triggered the unusual sorting rules of
      these locales.
     </para>
    </listitem>

    <listitem>
     <para>
      Update our copy of the timezone code to match
      IANA's <application>tzcode</application> release 2016c (Tom Lane)
     </para>

     <para>
      This is needed to cope with anticipated future changes in the time
      zone data files.  It also fixes some corner-case bugs in coping with
      unusual time zones.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2016f
      for DST law changes in Kemerovo and Novosibirsk, plus historical
      corrections for Azerbaijan, Belarus, and Morocco.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-13">
  <title>Release 9.3.13</title>

  <formalpara>
  <title>Release date:</title>
  <para>2016-05-12</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.12.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.13</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.9,
    see <xref linkend="release-9-3-9"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Clear the OpenSSL error queue before OpenSSL calls, rather than
      assuming it's clear already; and make sure we leave it clear
      afterwards (Peter Geoghegan, Dave Vitek, Peter Eisentraut)
     </para>

     <para>
      This change prevents problems when there are multiple connections
      using OpenSSL within a single process and not all the code involved
      follows the same rules for when to clear the error queue.
      Failures have been reported specifically when a client application
      uses SSL connections in <application>libpq</application> concurrently with
      SSL connections using the PHP, Python, or Ruby wrappers for OpenSSL.
      It's possible for similar problems to arise within the server as well,
      if an extension module establishes an outgoing SSL connection.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <quote>failed to build any <replaceable>N</replaceable>-way joins</quote>
      planner error with a full join enclosed in the right-hand side of a
      left join (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect handling of equivalence-class tests in multilevel
      nestloop plans (Tom Lane)
     </para>

     <para>
      Given a three-or-more-way equivalence class of variables, such
      as <literal>X.X = Y.Y = Z.Z</literal>, it was possible for the planner to omit
      some of the tests needed to enforce that all the variables are actually
      equal, leading to join rows being output that didn't satisfy
      the <literal>WHERE</literal> clauses.  For various reasons, erroneous plans
      were seldom selected in practice, so that this bug has gone undetected
      for a long time.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible misbehavior of <literal>TH</literal>, <literal>th</literal>,
      and <literal>Y,YYY</literal> format codes in <function>to_timestamp()</function>
      (Tom Lane)
     </para>

     <para>
      These could advance off the end of the input string, causing subsequent
      format codes to read garbage.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of rules and views in which the <replaceable>array</replaceable>
      argument of a <literal><replaceable>value</replaceable> <replaceable>operator</replaceable>
      ANY (<replaceable>array</replaceable>)</literal> construct is a sub-SELECT
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_regress</application> use a startup timeout from the
      <envar>PGCTLTIMEOUT</envar> environment variable, if that's set (Tom Lane)
     </para>

     <para>
      This is for consistency with a behavior recently added
      to <application>pg_ctl</application>; it eases automated testing on slow machines.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_upgrade</application> to correctly restore extension
      membership for operator families containing only one operator class
      (Tom Lane)
     </para>

     <para>
      In such a case, the operator family was restored into the new database,
      but it was no longer marked as part of the extension.  This had no
      immediate ill effects, but would cause later <application>pg_dump</application>
      runs to emit output that would cause (harmless) errors on restore.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_upgrade</application> to not fail when new-cluster TOAST rules
      differ from old (Tom Lane)
     </para>

     <para>
      <application>pg_upgrade</application> had special-case code to handle the
      situation where the new <productname>PostgreSQL</productname> version thinks that
      a table should have a TOAST table while the old version did not.  That
      code was broken, so remove it, and instead do nothing in such cases;
      there seems no reason to believe that we can't get along fine without
      a TOAST table if that was okay according to the old version's rules.
     </para>
    </listitem>

    <listitem>
<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [f4f4f6990] 2016-04-15 16:49:48 -0400
Branch: REL9_2_STABLE [d7dbc882d] 2016-04-15 16:49:48 -0400
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [992df9658] 2016-04-16 10:42:07 -0400
Branch: REL9_2_STABLE [9008922bf] 2016-04-16 10:41:57 -0400
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [35166fd76] 2016-04-18 13:19:52 -0400
Branch: REL9_2_STABLE [37f30b251] 2016-04-18 13:19:52 -0400
-->
     <para>
      Back-port 9.4-era memory-barrier code changes into 9.2 and 9.3 (Tom Lane)
     </para>

     <para>
      These changes were not originally needed in pre-9.4 branches, but we
      recently back-patched a fix that expected the barrier code to work
      properly.  Only IA64 (when using icc), HPPA, and Alpha platforms are
      affected.
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce the number of SysV semaphores used by a build configured with
      <option>--disable-spinlocks</option> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Rename internal function <function>strtoi()</function>
      to <function>strtoint()</function> to avoid conflict with a NetBSD library
      function (Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix reporting of errors from <function>bind()</function>
      and <function>listen()</function> system calls on Windows (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce verbosity of compiler output when building with Microsoft Visual
      Studio (Christian Ullrich)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>putenv()</function> to work properly with Visual Studio 2013
      (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid possibly-unsafe use of Windows' <function>FormatMessage()</function>
      function (Christian Ullrich)
     </para>

     <para>
      Use the <literal>FORMAT_MESSAGE_IGNORE_INSERTS</literal> flag where
      appropriate.  No live bug is known to exist here, but it seems like a
      good idea to be careful.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2016d
      for DST law changes in Russia and Venezuela.  There are new zone
      names <literal>Europe/Kirov</literal> and <literal>Asia/Tomsk</literal> to reflect
      the fact that these regions now have different time zone histories from
      adjacent regions.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-12">
  <title>Release 9.3.12</title>

  <formalpara>
  <title>Release date:</title>
  <para>2016-03-31</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.11.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.12</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.9,
    see <xref linkend="release-9-3-9"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix incorrect handling of NULL index entries in
      indexed <literal>ROW()</literal> comparisons (Tom Lane)
     </para>

     <para>
      An index search using a row comparison such as <literal>ROW(a, b) &gt;
      ROW('x', 'y')</literal> would stop upon reaching a NULL entry in
      the <structfield>b</structfield> column, ignoring the fact that there might be
      non-NULL <structfield>b</structfield> values associated with later values
      of <structfield>a</structfield>.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid unlikely data-loss scenarios due to renaming files without
      adequate <function>fsync()</function> calls before and after (Michael Paquier,
      Tomas Vondra, Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Correctly handle cases where <literal>pg_subtrans</literal> is close to XID
      wraparound during server startup (Jeff Janes)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix corner-case crash due to trying to free <function>localeconv()</function>
      output strings more than once (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix parsing of affix files for <literal>ispell</literal> dictionaries
      (Tom Lane)
     </para>

     <para>
      The code could go wrong if the affix file contained any characters
      whose byte length changes during case-folding, for
      example <literal>I</literal> in Turkish UTF8 locales.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid use of <function>sscanf()</function> to parse <literal>ispell</literal>
      dictionary files (Artur Zakirov)
     </para>

     <para>
      This dodges a portability problem on FreeBSD-derived platforms
      (including macOS).
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid a crash on old Windows versions (before 7SP1/2008R2SP1) with an
      AVX2-capable CPU and a Postgres build done with Visual Studio 2013
      (Christian Ullrich)
     </para>

     <para>
      This is a workaround for a bug in Visual Studio 2013's runtime
      library, which Microsoft have stated they will not fix in that
      version.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</application>'s tab completion logic to handle multibyte
      characters properly (Kyotaro Horiguchi, Robert Haas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</application>'s tab completion for
      <literal>SECURITY LABEL</literal> (Tom Lane)
     </para>

     <para>
      Pressing TAB after <literal>SECURITY LABEL</literal> might cause a crash
      or offering of inappropriate keywords.
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_ctl</application> accept a wait timeout from the
      <envar>PGCTLTIMEOUT</envar> environment variable, if none is specified on
      the command line (Noah Misch)
     </para>

     <para>
      This eases testing of slower buildfarm members by allowing them
      to globally specify a longer-than-normal timeout for postmaster
      startup and shutdown.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect test for Windows service status
      in <application>pg_ctl</application> (Manuel Mathar)
     </para>

     <para>
      The previous set of minor releases attempted to
      fix <application>pg_ctl</application> to properly determine whether to send log
      messages to Window's Event Log, but got the test backwards.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pgbench</application> to correctly handle the combination
      of <literal>-C</literal> and <literal>-M prepared</literal> options (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_upgrade</application>, skip creating a deletion script when
      the new data directory is inside the old data directory (Bruce
      Momjian)
     </para>

     <para>
      Blind application of the script in such cases would result in loss of
      the new data directory.
     </para>
    </listitem>

    <listitem>
     <para>
      In PL/Perl, properly translate empty Postgres arrays into empty Perl
      arrays (Alex Hunsaker)
     </para>
    </listitem>

    <listitem>
     <para>
      Make PL/Python cope with function names that aren't valid Python
      identifiers (Jim Nasby)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix multiple mistakes in the statistics returned
      by <filename>contrib/pgstattuple</filename>'s <function>pgstatindex()</function>
      function (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Remove dependency on <literal>psed</literal> in MSVC builds, since it's no
      longer provided by core Perl (Michael Paquier, Andrew Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2016c
      for DST law changes in Azerbaijan, Chile, Haiti, Palestine, and Russia
      (Altai, Astrakhan, Kirov, Sakhalin, Ulyanovsk regions), plus
      historical corrections for Lithuania, Moldova, and Russia
      (Kaliningrad, Samara, Volgograd).
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-11">
  <title>Release 9.3.11</title>

  <formalpara>
  <title>Release date:</title>
  <para>2016-02-11</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.10.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.11</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.9,
    see <xref linkend="release-9-3-9"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix infinite loops and buffer-overrun problems in regular expressions
      (Tom Lane)
     </para>

     <para>
      Very large character ranges in bracket expressions could cause
      infinite loops in some cases, and memory overwrites in other cases.
      (CVE-2016-0773)
     </para>
    </listitem>

    <listitem>
     <para>
      Perform an immediate shutdown if the <filename>postmaster.pid</filename> file
      is removed (Tom Lane)
     </para>

     <para>
      The postmaster now checks every minute or so
      that <filename>postmaster.pid</filename> is still there and still contains its
      own PID.  If not, it performs an immediate shutdown, as though it had
      received <systemitem>SIGQUIT</systemitem>.  The main motivation for this change
      is to ensure that failed buildfarm runs will get cleaned up without
      manual intervention; but it also serves to limit the bad effects if a
      DBA forcibly removes <filename>postmaster.pid</filename> and then starts a new
      postmaster.
     </para>
    </listitem>

    <listitem>
     <para>
      In <literal>SERIALIZABLE</literal> transaction isolation mode, serialization
      anomalies could be missed due to race conditions during insertions
      (Kevin Grittner, Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix failure to emit appropriate WAL records when doing <literal>ALTER
      TABLE ... SET TABLESPACE</literal> for unlogged relations (Michael Paquier,
      Andres Freund)
     </para>

     <para>
      Even though the relation's data is unlogged, the move must be logged or
      the relation will be inaccessible after a standby is promoted to master.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible misinitialization of unlogged relations at the end of
      crash recovery (Andres Freund, Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure walsender slots are fully re-initialized when being re-used
      (Magnus Hagander)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>ALTER COLUMN TYPE</command> to reconstruct inherited check
      constraints properly (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</command> to change ownership of composite types
      properly (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</command> and <command>ALTER OWNER</command> to correctly
      update granted-permissions lists when changing owners of data types,
      foreign data wrappers, or foreign servers (Bruce Momjian,
      &Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</command> to ignore foreign user mappings,
      rather than fail (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible crash after doing query rewrite for an updatable view
      (Stephen Frost)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix planner's handling of <literal>LATERAL</literal> references (Tom
      Lane)
     </para>

     <para>
      This fixes some corner cases that led to <quote>failed to build any
      N-way joins</quote> or <quote>could not devise a query plan</quote> planner
      failures.
     </para>
    </listitem>

    <listitem>
     <para>
      Add more defenses against bad planner cost estimates for GIN index
      scans when the index's internal statistics are very out-of-date
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make planner cope with hypothetical GIN indexes suggested by an index
      advisor plug-in (Julien Rouhaud)
     </para>
    </listitem>

    <listitem>
     <para>
      Speed up generation of unique table aliases in <command>EXPLAIN</command> and
      rule dumping, and ensure that generated aliases do not
      exceed <literal>NAMEDATALEN</literal> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of whole-row Vars in <literal>ROW()</literal>
      and <literal>VALUES()</literal> lists (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible internal overflow in <type>numeric</type> division
      (Dean Rasheed)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix enforcement of restrictions inside parentheses within regular
      expression lookahead constraints (Tom Lane)
     </para>

     <para>
      Lookahead constraints aren't allowed to contain backrefs, and
      parentheses within them are always considered non-capturing, according
      to the manual.  However, the code failed to handle these cases properly
      inside a parenthesized subexpression, and would give unexpected
      results.
     </para>
    </listitem>

    <listitem>
     <para>
      Conversion of regular expressions to indexscan bounds could produce
      incorrect bounds from regexps containing lookahead constraints
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix regular-expression compiler to handle loops of constraint arcs
      (Tom Lane)
     </para>

     <para>
      The code added for CVE-2007-4772 was both incomplete, in that it didn't
      handle loops involving more than one state, and incorrect, in that it
      could cause assertion failures (though there seem to be no bad
      consequences of that in a non-assert build).  Multi-state loops would
      cause the compiler to run until the query was canceled or it reached
      the too-many-states error condition.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve memory-usage accounting in regular-expression compiler
      (Tom Lane)
     </para>

     <para>
      This causes the code to emit <quote>regular expression is too
      complex</quote> errors in some cases that previously used unreasonable
      amounts of time and memory.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve performance of regular-expression compiler (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <literal>%h</literal> and <literal>%r</literal> escapes
      in <varname>log_line_prefix</varname> work for messages emitted due
      to <varname>log_connections</varname> (Tom Lane)
     </para>

     <para>
      Previously, <literal>%h</literal>/<literal>%r</literal> started to work just after a
      new session had emitted the <quote>connection received</quote> log message;
      now they work for that message too.
     </para>
    </listitem>

    <listitem>
     <para>
      On Windows, ensure the shared-memory mapping handle gets closed in
      child processes that don't need it (Tom Lane, Amit Kapila)
     </para>

     <para>
      This oversight resulted in failure to recover from crashes
      whenever <varname>logging_collector</varname> is turned on.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible failure to detect socket EOF in non-blocking mode on
      Windows (Tom Lane)
     </para>

     <para>
      It's not entirely clear whether this problem can happen in pre-9.5
      branches, but if it did, the symptom would be that a walsender process
      would wait indefinitely rather than noticing a loss of connection.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid leaking a token handle during SSPI authentication
      (Christian Ullrich)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>psql</application>, ensure that <application>libreadline</application>'s idea
      of the screen size is updated when the terminal window size changes
      (Merlin Moncure)
     </para>

     <para>
      Previously, <application>libreadline</application> did not notice if the window
      was resized during query output, leading to strange behavior during
      later input of multiline queries.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</application>'s <literal>\det</literal> command to interpret its
      pattern argument the same way as other <literal>\d</literal> commands with
      potentially schema-qualified patterns do (Reece Hart)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid possible crash in <application>psql</application>'s <literal>\c</literal> command
      when previous connection was via Unix socket and command specifies a
      new hostname and same username (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      In <literal>pg_ctl start -w</literal>, test child process status directly
      rather than relying on heuristics (Tom Lane, Michael Paquier)
     </para>

     <para>
      Previously, <application>pg_ctl</application> relied on an assumption that the new
      postmaster would always create <filename>postmaster.pid</filename> within five
      seconds.  But that can fail on heavily-loaded systems,
      causing <application>pg_ctl</application> to report incorrectly that the
      postmaster failed to start.
     </para>

     <para>
      Except on Windows, this change also means that a <literal>pg_ctl start
      -w</literal> done immediately after another such command will now reliably
      fail, whereas previously it would report success if done within two
      seconds of the first command.
     </para>
    </listitem>

    <listitem>
     <para>
      In <literal>pg_ctl start -w</literal>, don't attempt to use a wildcard listen
      address to connect to the postmaster (Kondo Yuta)
     </para>

     <para>
      On Windows, <application>pg_ctl</application> would fail to detect postmaster
      startup if <varname>listen_addresses</varname> is set to <literal>0.0.0.0</literal>
      or <literal>::</literal>, because it would try to use that value verbatim as
      the address to connect to, which doesn't work.  Instead assume
      that <literal>127.0.0.1</literal> or <literal>::1</literal>, respectively, is the
      right thing to use.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_ctl</application> on Windows, check service status to decide
      where to send output, rather than checking if standard output is a
      terminal (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</application> and <application>pg_basebackup</application>, adopt
      the GNU convention for handling tar-archive members exceeding 8GB
      (Tom Lane)
     </para>

     <para>
      The POSIX standard for <literal>tar</literal> file format does not allow
      archive member files to exceed 8GB, but most modern implementations
      of <application>tar</application> support an extension that fixes that.  Adopt
      this extension so that <application>pg_dump</application> with <option>-Ft</option> no
      longer fails on tables with more than 8GB of data, and so
      that <application>pg_basebackup</application> can handle files larger than 8GB.
      In addition, fix some portability issues that could cause failures for
      members between 4GB and 8GB on some platforms.  Potentially these
      problems could cause unrecoverable data loss due to unreadable backup
      files.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix assorted corner-case bugs in <application>pg_dump</application>'s processing
      of extension member objects (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_dump</application> mark a view's triggers as needing to be
      processed after its rule, to prevent possible failure during
      parallel <application>pg_restore</application> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that relation option values are properly quoted
      in <application>pg_dump</application> (Kouhei Sutou, Tom Lane)
     </para>

     <para>
      A reloption value that isn't a simple identifier or number could lead
      to dump/reload failures due to syntax errors in CREATE statements
      issued by <application>pg_dump</application>.  This is not an issue with any
      reloption currently supported by core <productname>PostgreSQL</productname>, but
      extensions could allow reloptions that cause the problem.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid repeated password prompts during parallel <application>pg_dump</application>
      (Zeus Kronion)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_upgrade</application>'s file-copying code to handle errors
      properly on Windows (Bruce Momjian)
     </para>
    </listitem>

    <listitem>
     <para>
      Install guards in <application>pgbench</application> against corner-case overflow
      conditions during evaluation of script-specified division or modulo
      operators (Fabien Coelho, Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix failure to localize messages emitted
      by <application>pg_receivexlog</application> and <application>pg_recvlogical</application>
      (Ioseph Kim)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid dump/reload problems when using both <application>plpython2</application>
      and <application>plpython3</application> (Tom Lane)
     </para>

     <para>
      In principle, both versions of <application>PL/Python</application> can be used in
      the same database, though not in the same session (because the two
      versions of <application>libpython</application> cannot safely be used concurrently).
      However, <application>pg_restore</application> and <application>pg_upgrade</application> both
      do things that can fall foul of the same-session restriction.  Work
      around that by changing the timing of the check.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>PL/Python</application> regression tests to pass with Python 3.5
      (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix premature clearing of <application>libpq</application>'s input buffer when
      socket EOF is seen (Tom Lane)
     </para>

     <para>
      This mistake caused <application>libpq</application> to sometimes not report the
      backend's final error message before reporting <quote>server closed the
      connection unexpectedly</quote>.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent certain <application>PL/Java</application> parameters from being set by
      non-superusers (Noah Misch)
     </para>

     <para>
      This change mitigates a <application>PL/Java</application> security bug
      (CVE-2016-0766), which was fixed in <application>PL/Java</application> by marking
      these parameters as superuser-only.  To fix the security hazard for
      sites that update <productname>PostgreSQL</productname> more frequently
      than <application>PL/Java</application>, make the core code aware of them also.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve <application>libpq</application>'s handling of out-of-memory situations
      (Michael Paquier, Amit Kapila, Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix order of arguments
      in <application>ecpg</application>-generated <literal>typedef</literal> statements
      (Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      Use <literal>%g</literal> not <literal>%f</literal> format
      in <application>ecpg</application>'s <function>PGTYPESnumeric_from_double()</function>
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application>-supplied header files to not contain comments
      continued from a preprocessor directive line onto the next line
      (Michael Meskes)
     </para>

     <para>
      Such a comment is rejected by <application>ecpg</application>.  It's not yet clear
      whether <application>ecpg</application> itself should be changed.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>hstore_to_json_loose()</function>'s test for whether
      an <type>hstore</type> value can be converted to a JSON number (Tom Lane)
     </para>

     <para>
      Previously this function could be fooled by non-alphanumeric trailing
      characters, leading to emitting syntactically-invalid JSON.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that <filename>contrib/pgcrypto</filename>'s <function>crypt()</function>
      function can be interrupted by query cancel (Andreas Karlsson)
     </para>
    </listitem>

    <listitem>
     <para>
      Accept <application>flex</application> versions later than 2.5.x
      (Tom Lane, Michael Paquier)
     </para>

     <para>
      Now that flex 2.6.0 has been released, the version checks in our build
      scripts needed to be adjusted.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve reproducibility of build output by ensuring filenames are given
      to the linker in a fixed order (Christoph Berg)
     </para>

     <para>
      This avoids possible bitwise differences in the produced executable
      files from one build to the next.
     </para>
    </listitem>

    <listitem>
     <para>
      Install our <filename>missing</filename> script where PGXS builds can find it
      (Jim Nasby)
     </para>

     <para>
      This allows sane behavior in a PGXS build done on a machine where build
      tools such as <application>bison</application> are missing.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that <filename>dynloader.h</filename> is included in the installed
      header files in MSVC builds (Bruce Momjian, Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Add variant regression test expected-output file to match behavior of
      current <application>libxml2</application> (Tom Lane)
     </para>

     <para>
      The fix for <application>libxml2</application>'s CVE-2015-7499 causes it not to
      output error context reports in some cases where it used to do so.
      This seems to be a bug, but we'll probably have to live with it for
      some time, so work around it.
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2016a for
      DST law changes in Cayman Islands, Metlakatla, and Trans-Baikal
      Territory (Zabaykalsky Krai), plus historical corrections for Pakistan.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-10">
  <title>Release 9.3.10</title>

  <formalpara>
  <title>Release date:</title>
  <para>2015-10-08</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.9.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.10</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.9,
    see <xref linkend="release-9-3-9"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Guard against stack overflows in <type>json</type> parsing
      (Oskari Saarenmaa)
     </para>

     <para>
      If an application constructs PostgreSQL <type>json</type>
      or <type>jsonb</type> values from arbitrary user input, the application's
      users can reliably crash the PostgreSQL server, causing momentary
      denial of service.  (CVE-2015-5289)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <filename>contrib/pgcrypto</filename> to detect and report
      too-short <function>crypt()</function> salts (Josh Kupershmidt)
     </para>

     <para>
      Certain invalid salt arguments crashed the server or disclosed a few
      bytes of server memory.  We have not ruled out the viability of
      attacks that arrange for presence of confidential information in the
      disclosed bytes, but they seem unlikely.  (CVE-2015-5288)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix subtransaction cleanup after a portal (cursor) belonging to an
      outer subtransaction fails (Tom Lane, Michael Paquier)
     </para>

     <para>
      A function executed in an outer-subtransaction cursor could cause an
      assertion failure or crash by referencing a relation created within an
      inner subtransaction.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure all relations referred to by an updatable view are properly
      locked during an update statement (Dean Rasheed)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix insertion of relations into the relation cache <quote>init file</quote>
      (Tom Lane)
     </para>

     <para>
      An oversight in a patch in the most recent minor releases
      caused <structname>pg_trigger_tgrelid_tgname_index</structname> to be omitted
      from the init file.  Subsequent sessions detected this, then deemed the
      init file to be broken and silently ignored it, resulting in a
      significant degradation in session startup time.  In addition to fixing
      the bug, install some guards so that any similar future mistake will be
      more obvious.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid O(N^2) behavior when inserting many tuples into a SPI query
      result (Neil Conway)
     </para>
    </listitem>

    <listitem>
     <para>
      Improve <command>LISTEN</command> startup time when there are many unread
      notifications (Matt Newell)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix performance problem when a session alters large numbers of foreign
      key constraints (Jan Wieck, Tom Lane)
     </para>

     <para>
      This was seen primarily when restoring <application>pg_dump</application> output
      for databases with many thousands of tables.
     </para>
    </listitem>

    <listitem>
     <para>
      Disable SSL renegotiation by default (Michael Paquier, Andres Freund)
     </para>

     <para>
      While use of SSL renegotiation is a good idea in theory, we have seen
      too many bugs in practice, both in the underlying OpenSSL library and
      in our usage of it.  Renegotiation will be removed entirely in 9.5 and
      later.  In the older branches, just change the default value
      of <varname>ssl_renegotiation_limit</varname> to zero (disabled).
     </para>
    </listitem>

    <listitem>
     <para>
      Lower the minimum values of the <literal>*_freeze_max_age</literal> parameters
      (Andres Freund)
     </para>

     <para>
      This is mainly to make tests of related behavior less time-consuming,
      but it may also be of value for installations with limited disk space.
     </para>
    </listitem>

    <listitem>
     <para>
      Limit the maximum value of <varname>wal_buffers</varname> to 2GB to avoid
      server crashes (Josh Berkus)
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid logging complaints when a parameter that can only be set at
      server start appears multiple times in <filename>postgresql.conf</filename>,
      and fix counting of line numbers after an <literal>include_dir</literal>
      directive (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix rare internal overflow in multiplication of <type>numeric</type> values
      (Dean Rasheed)
     </para>
    </listitem>

    <listitem>
     <para>
      Guard against hard-to-reach stack overflows involving record types,
      range types, <type>json</type>, <type>jsonb</type>, <type>tsquery</type>,
      <type>ltxtquery</type> and <type>query_int</type> (Noah Misch)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix handling of <literal>DOW</literal> and <literal>DOY</literal> in datetime input
      (Greg Stark)
     </para>

     <para>
      These tokens aren't meant to be used in datetime values, but previously
      they resulted in opaque internal error messages rather
      than <quote>invalid input syntax</quote>.
     </para>
    </listitem>

    <listitem>
     <para>
      Add more query-cancel checks to regular expression matching (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Add recursion depth protections to regular expression, <literal>SIMILAR
      TO</literal>, and <literal>LIKE</literal> matching (Tom Lane)
     </para>

     <para>
      Suitable search patterns and a low stack depth limit could lead to
      stack-overrun crashes.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix potential infinite loop in regular expression execution (Tom Lane)
     </para>

     <para>
      A search pattern that can apparently match a zero-length string, but
      actually doesn't match because of a back reference, could lead to an
      infinite loop.
     </para>
    </listitem>

    <listitem>
     <para>
      In regular expression execution, correctly record match data for
      capturing parentheses within a quantifier even when the match is
      zero-length (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix low-memory failures in regular expression compilation
      (Andreas Seltenreich)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix low-probability memory leak during regular expression execution
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix rare low-memory failure in lock cleanup during transaction abort
      (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <quote>unexpected out-of-memory situation during sort</quote> errors
      when using tuplestores with small <varname>work_mem</varname> settings (Tom
      Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix very-low-probability stack overrun in <function>qsort</function> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <quote>invalid memory alloc request size</quote> failure in hash joins
      with large <varname>work_mem</varname> settings (Tomas Vondra, Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix assorted planner bugs (Tom Lane)
     </para>

     <para>
      These mistakes could lead to incorrect query plans that would give wrong
      answers, or to assertion failures in assert-enabled builds, or to odd
      planner errors such as <quote>could not devise a query plan for the
      given query</quote>, <quote>could not find pathkey item to
      sort</quote>, <quote>plan should not reference subplan's variable</quote>,
      or <quote>failed to assign all NestLoopParams to plan nodes</quote>.
      Thanks are due to Andreas Seltenreich and Piotr Stefaniak for fuzz
      testing that exposed these problems.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve planner's performance for <command>UPDATE</command>/<command>DELETE</command>
      on large inheritance sets (Tom Lane, Dean Rasheed)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure standby promotion trigger files are removed at postmaster
      startup (Michael Paquier, Fujii Masao)
     </para>

     <para>
      This prevents unwanted promotion from occurring if these files appear
      in a database backup that is used to initialize a new standby server.
     </para>
    </listitem>

    <listitem>
     <para>
      During postmaster shutdown, ensure that per-socket lock files are
      removed and listen sockets are closed before we remove
      the <filename>postmaster.pid</filename> file (Tom Lane)
     </para>

     <para>
      This avoids race-condition failures if an external script attempts to
      start a new postmaster as soon as <literal>pg_ctl stop</literal> returns.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix postmaster's handling of a startup-process crash during crash
      recovery (Tom Lane)
     </para>

     <para>
      If, during a crash recovery cycle, the startup process crashes without
      having restored database consistency, we'd try to launch a new startup
      process, which typically would just crash again, leading to an infinite
      loop.
     </para>
    </listitem>

    <listitem>
     <para>
      Make emergency autovacuuming for multixact wraparound more robust
      (Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Do not print a <literal>WARNING</literal> when an autovacuum worker is already
      gone when we attempt to signal it, and reduce log verbosity for such
      signals (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent autovacuum launcher from sleeping unduly long if the server
      clock is moved backwards a large amount (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that cleanup of a GIN index's pending-insertions list is
      interruptable by cancel requests (Jeff Janes)
     </para>
    </listitem>

    <listitem>
     <para>
      Allow all-zeroes pages in GIN indexes to be reused (Heikki Linnakangas)
     </para>

     <para>
      Such a page might be left behind after a crash.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix handling of all-zeroes pages in SP-GiST indexes (Heikki
      Linnakangas)
     </para>

     <para>
      <command>VACUUM</command> attempted to recycle such pages, but did so in a
      way that wasn't crash-safe.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix off-by-one error that led to otherwise-harmless warnings
      about <quote>apparent wraparound</quote> in subtrans/multixact truncation
      (Thomas Munro)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix misreporting of <command>CONTINUE</command> and <command>MOVE</command> statement
      types in <application>PL/pgSQL</application>'s error context messages
      (Pavel Stehule, Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>PL/Perl</application> to handle non-<acronym>ASCII</acronym> error
      message texts correctly (Alex Hunsaker)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>PL/Python</application> crash when returning the string
      representation of a <type>record</type> result (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix some places in <application>PL/Tcl</application> that neglected to check for
      failure of <function>malloc()</function> calls (Michael Paquier, &Aacute;lvaro
      Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      In <filename>contrib/isn</filename>, fix output of ISBN-13 numbers that begin
      with 979 (Fabien Coelho)
     </para>

     <para>
      EANs beginning with 979 (but not 9790) are considered ISBNs, but they
      must be printed in the new 13-digit format, not the 10-digit format.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve <filename>contrib/postgres_fdw</filename>'s handling of
      collation-related decisions (Tom Lane)
     </para>

     <para>
      The main user-visible effect is expected to be that comparisons
      involving <type>varchar</type> columns will be sent to the remote server
      for execution in more cases than before.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve <application>libpq</application>'s handling of out-of-memory conditions
      (Michael Paquier, Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix memory leaks and missing out-of-memory checks
      in <application>ecpg</application> (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</application>'s code for locale-aware formatting of numeric
      output (Tom Lane)
     </para>

     <para>
      The formatting code invoked by <literal>\pset numericlocale on</literal>
      did the wrong thing for some uncommon cases such as numbers with an
      exponent but no decimal point.  It could also mangle already-localized
      output from the <type>money</type> data type.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent crash in <application>psql</application>'s <command>\c</command> command when
      there is no current connection (Noah Misch)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_dump</application> handle inherited <literal>NOT VALID</literal>
      check constraints correctly (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix selection of default <application>zlib</application> compression level
      in <application>pg_dump</application>'s directory output format (Andrew Dunstan)
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure that temporary files created during a <application>pg_dump</application>
      run with <acronym>tar</acronym>-format output are not world-readable (Michael
      Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> and <application>pg_upgrade</application> to support
      cases where the <literal>postgres</literal> or <literal>template1</literal> database
      is in a non-default tablespace (Marti Raudsepp, Bruce Momjian)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> to handle object privileges sanely when
      dumping from a server too old to have a particular privilege type
      (Tom Lane)
     </para>

     <para>
      When dumping data types from pre-9.2 servers, and when dumping
      functions or procedural languages from pre-7.3
      servers, <application>pg_dump</application> would
      produce <command>GRANT</command>/<command>REVOKE</command> commands that revoked the
      owner's grantable privileges and instead granted all privileges
      to <literal>PUBLIC</literal>.  Since the privileges involved are
      just <literal>USAGE</literal> and <literal>EXECUTE</literal>, this isn't a security
      problem, but it's certainly a surprising representation of the older
      systems' behavior.  Fix it to leave the default privilege state alone
      in these cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application> to dump shell types (Tom Lane)
     </para>

     <para>
      Shell types (that is, not-yet-fully-defined types) aren't useful for
      much, but nonetheless <application>pg_dump</application> should dump them.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix assorted minor memory leaks in <application>pg_dump</application> and other
      client-side programs (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix spinlock assembly code for PPC hardware to be compatible
      with <acronym>AIX</acronym>'s native assembler (Tom Lane)
     </para>

     <para>
      Building with <application>gcc</application> didn't work if <application>gcc</application>
      had been configured to use the native assembler, which is becoming more
      common.
     </para>
    </listitem>

    <listitem>
     <para>
      On <acronym>AIX</acronym>, test the <literal>-qlonglong</literal> compiler option
      rather than just assuming it's safe to use (Noah Misch)
     </para>
    </listitem>

    <listitem>
     <para>
      On <acronym>AIX</acronym>, use <literal>-Wl,-brtllib</literal> link option to allow
      symbols to be resolved at runtime (Noah Misch)
     </para>

     <para>
      Perl relies on this ability in 5.8.0 and later.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid use of inline functions when compiling with
      32-bit <application>xlc</application>, due to compiler bugs (Noah Misch)
     </para>
    </listitem>

    <listitem>
     <para>
      Use <filename>librt</filename> for <function>sched_yield()</function> when necessary,
      which it is on some Solaris versions (Oskari Saarenmaa)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix Windows <filename>install.bat</filename> script to handle target directory
      names that contain spaces (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Make the numeric form of the <productname>PostgreSQL</productname> version number
      (e.g., <literal>90405</literal>) readily available to extension Makefiles,
      as a variable named <varname>VERSION_NUM</varname> (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2015g for
      DST law changes in Cayman Islands, Fiji, Moldova, Morocco, Norfolk
      Island, North Korea, Turkey, and Uruguay.  There is a new zone name
      <literal>America/Fort_Nelson</literal> for the Canadian Northern Rockies.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-9">
  <title>Release 9.3.9</title>

  <formalpara>
  <title>Release date:</title>
  <para>2015-06-12</para>
  </formalpara>

  <para>
   This release contains a small number of fixes from 9.3.8.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.9</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading an installation that was previously
    upgraded using a <application>pg_upgrade</application> version between 9.3.0 and
    9.3.4 inclusive, see the first changelog entry below.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.7,
    see <xref linkend="release-9-3-7"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix possible failure to recover from an inconsistent database state
      (Robert Haas)
     </para>

     <para>
      Recent <productname>PostgreSQL</productname> releases introduced mechanisms to
      protect against multixact wraparound, but some of that code did not
      account for the possibility that it would need to run during crash
      recovery, when the database may not be in a consistent state.  This
      could result in failure to restart after a crash, or failure to start
      up a secondary server.  The lingering effects of a previously-fixed
      bug in <application>pg_upgrade</application> could also cause such a failure, in
      installations that had used <application>pg_upgrade</application> versions
      between 9.3.0 and 9.3.4.
     </para>

     <para>
      The <application>pg_upgrade</application> bug in question was that it would
      set <literal>oldestMultiXid</literal> to 1 in <filename>pg_control</filename> even
      if the true value should be higher.  With the fixes introduced in
      this release, such a situation will result in immediate emergency
      autovacuuming until a correct <literal>oldestMultiXid</literal> value can be
      determined.  If that would pose a hardship, users can avoid it by
      doing manual vacuuming <emphasis>before</emphasis> upgrading to this release.
      In detail:

      <orderedlist>
       <listitem>
        <para>
         Check whether <application>pg_controldata</application> reports <quote>Latest
         checkpoint's oldestMultiXid</quote> to be 1.  If not, there's nothing
         to do.
        </para>
       </listitem>
       <listitem>
        <para>
         Look in <filename>PGDATA/pg_multixact/offsets</filename> to see if there's a
         file named <filename>0000</filename>.  If there is, there's nothing to do.
        </para>
       </listitem>
       <listitem>
        <para>
         Otherwise, for each table that has
         <structname>pg_class</structname>.<structfield>relminmxid</structfield> equal to 1,
         <command>VACUUM</command> that table with
         both <xref linkend="guc-vacuum-multixact-freeze-min-age"/>
         and <xref linkend="guc-vacuum-multixact-freeze-table-age"/> set to
         zero.  (You can use the vacuum cost delay parameters described
         in <xref linkend="runtime-config-resource-vacuum-cost"/> to reduce
         the performance consequences for concurrent sessions.)  You must
         use <productname>PostgreSQL</productname> 9.3.5 or later to perform this step.
        </para>
       </listitem>
      </orderedlist>
     </para>
    </listitem>

    <listitem>
     <para>
      Fix rare failure to invalidate relation cache init file (Tom Lane)
     </para>

     <para>
      With just the wrong timing of concurrent activity, a <command>VACUUM
      FULL</command> on a system catalog might fail to update the <quote>init file</quote>
      that's used to avoid cache-loading work for new sessions.  This would
      result in later sessions being unable to access that catalog at all.
      This is a very ancient bug, but it's so hard to trigger that no
      reproducible case had been seen until recently.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid deadlock between incoming sessions and <literal>CREATE/DROP
      DATABASE</literal> (Tom Lane)
     </para>

     <para>
      A new session starting in a database that is the target of
      a <command>DROP DATABASE</command> command, or is the template for
      a <command>CREATE DATABASE</command> command, could cause the command to wait
      for five seconds and then fail, even if the new session would have
      exited before that.
     </para>
    </listitem>

    <listitem>
     <para>
      Improve planner's cost estimates for semi-joins and anti-joins with
      inner indexscans (Tom Lane, Tomas Vondra)
     </para>

     <para>
      This type of plan is quite cheap when all the join clauses are used
      as index scan conditions, even if the inner scan would nominally
      fetch many rows, because the executor will stop after obtaining one
      row.  The planner only partially accounted for that effect, and would
      therefore overestimate the cost, leading it to possibly choose some
      other much less efficient plan type.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-8">
  <title>Release 9.3.8</title>

  <formalpara>
  <title>Release date:</title>
  <para>2015-06-04</para>
  </formalpara>

  <para>
   This release contains a small number of fixes from 9.3.7.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.8</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are upgrading from a version earlier than 9.3.7,
    see <xref linkend="release-9-3-7"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Avoid failures while <function>fsync</function>'ing data directory during
      crash restart (Abhijit Menon-Sen, Tom Lane)
     </para>

     <para>
      In the previous minor releases we added a patch to <function>fsync</function>
      everything in the data directory after a crash.  Unfortunately its
      response to any error condition was to fail, thereby preventing the
      server from starting up, even when the problem was quite harmless.
      An example is that an unwritable file in the data directory would
      prevent restart on some platforms; but it is common to make SSL
      certificate files unwritable by the server.  Revise this behavior so
      that permissions failures are ignored altogether, and other types of
      failures are logged but do not prevent continuing.
     </para>

     <para>
      Also apply the same rules in <literal>initdb --sync-only</literal>.
      This case is less critical but it should act similarly.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <function>pg_get_functiondef()</function> to show
      functions' <literal>LEAKPROOF</literal> property, if set (Jeevan Chalke)
     </para>
    </listitem>

    <listitem>
     <para>
      Remove <application>configure</application>'s check prohibiting linking to a
      threaded <application>libpython</application>
      on <systemitem class="osname">OpenBSD</systemitem> (Tom Lane)
     </para>

     <para>
      The failure this restriction was meant to prevent seems to not be a
      problem anymore on current <systemitem class="osname">OpenBSD</systemitem>
      versions.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [c6b7b9a9c] 2015-05-21 20:41:55 -0400
Branch: REL9_2_STABLE [b78fbfe65] 2015-05-21 20:41:55 -0400
Branch: REL9_1_STABLE [2c2c5f0e0] 2015-05-21 20:41:55 -0400
Branch: REL9_0_STABLE [4dddf8552] 2015-05-21 20:41:55 -0400
-->

    <listitem>
     <para>
      Allow <application>libpq</application> to use TLS protocol versions beyond v1
      (Noah Misch)
     </para>

     <para>
      For a long time, <application>libpq</application> was coded so that the only SSL
      protocol it would allow was TLS v1.  Now that newer TLS versions are
      becoming popular, allow it to negotiate the highest commonly-supported
      TLS version with the server.  (<productname>PostgreSQL</productname> servers were
      already capable of such negotiation, so no change is needed on the
      server side.)  This is a back-patch of a change already released in
      9.4.0.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-7">
  <title>Release 9.3.7</title>

  <formalpara>
  <title>Release date:</title>
  <para>2015-05-22</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.6.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.7</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you use <filename>contrib/citext</filename>'s
    <function>regexp_matches()</function> functions, see the changelog entry below
    about that.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.6,
    see <xref linkend="release-9-3-6"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Avoid possible crash when client disconnects just before the
      authentication timeout expires (Benkocs Norbert Attila)
     </para>

     <para>
      If the timeout interrupt fired partway through the session shutdown
      sequence, SSL-related state would be freed twice, typically causing a
      crash and hence denial of service to other sessions.  Experimentation
      shows that an unauthenticated remote attacker could trigger the bug
      somewhat consistently, hence treat as security issue.
      (CVE-2015-3165)
     </para>
    </listitem>

    <listitem>
     <para>
      Improve detection of system-call failures (Noah Misch)
     </para>

     <para>
      Our replacement implementation of <function>snprintf()</function> failed to
      check for errors reported by the underlying system library calls;
      the main case that might be missed is out-of-memory situations.
      In the worst case this might lead to information exposure, due to our
      code assuming that a buffer had been overwritten when it hadn't been.
      Also, there were a few places in which security-relevant calls of other
      system library functions did not check for failure.
     </para>

     <para>
      It remains possible that some calls of the <function>*printf()</function>
      family of functions are vulnerable to information disclosure if an
      out-of-memory error occurs at just the wrong time.  We judge the risk
      to not be large, but will continue analysis in this area.
      (CVE-2015-3166)
     </para>
    </listitem>

    <listitem>
     <para>
      In <filename>contrib/pgcrypto</filename>, uniformly report decryption failures
      as <quote>Wrong key or corrupt data</quote> (Noah Misch)
     </para>

     <para>
      Previously, some cases of decryption with an incorrect key could report
      other error message texts.  It has been shown that such variance in
      error reports can aid attackers in recovering keys from other systems.
      While it's unknown whether <filename>pgcrypto</filename>'s specific behaviors
      are likewise exploitable, it seems better to avoid the risk by using a
      one-size-fits-all message.
      (CVE-2015-3167)
     </para>
    </listitem>

    <listitem>
     <para>
      Protect against wraparound of multixact member IDs
      (&Aacute;lvaro Herrera, Robert Haas, Thomas Munro)
     </para>

     <para>
      Under certain usage patterns, the existing defenses against this might
      be insufficient, allowing <filename>pg_multixact/members</filename> files to be
      removed too early, resulting in data loss.
      The fix for this includes modifying the server to fail transactions
      that would result in overwriting old multixact member ID data, and
      improving autovacuum to ensure it will act proactively to prevent
      multixact member ID wraparound, as it does for transaction ID
      wraparound.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect declaration of <filename>contrib/citext</filename>'s
      <function>regexp_matches()</function> functions (Tom Lane)
     </para>

     <para>
      These functions should return <type>setof text[]</type>, like the core
      functions they are wrappers for; but they were incorrectly declared as
      returning just <type>text[]</type>.  This mistake had two results: first,
      if there was no match you got a scalar null result, whereas what you
      should get is an empty set (zero rows).  Second, the <literal>g</literal> flag
      was effectively ignored, since you would get only one result array even
      if there were multiple matches.
     </para>

     <para>
      While the latter behavior is clearly a bug, there might be applications
      depending on the former behavior; therefore the function declarations
      will not be changed by default until <productname>PostgreSQL</productname> 9.5.
      In pre-9.5 branches, the old behavior exists in version 1.0 of
      the <literal>citext</literal> extension, while we have provided corrected
      declarations in version 1.1 (which is <emphasis>not</emphasis> installed by
      default).  To adopt the fix in pre-9.5 branches, execute
      <literal>ALTER EXTENSION citext UPDATE TO '1.1'</literal> in each database in
      which <literal>citext</literal> is installed.  (You can also <quote>update</quote>
      back to 1.0 if you need to undo that.)  Be aware that either update
      direction will require dropping and recreating any views or rules that
      use <filename>citext</filename>'s <function>regexp_matches()</function> functions.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect checking of deferred exclusion constraints after a HOT
      update (Tom Lane)
     </para>

     <para>
      If a new row that potentially violates a deferred exclusion constraint
      is HOT-updated (that is, no indexed columns change and the row can be
      stored back onto the same table page) later in the same transaction,
      the exclusion constraint would be reported as violated when the check
      finally occurred, even if the row(s) the new row originally conflicted
      with had been deleted.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix planning of star-schema-style queries (Tom Lane)
     </para>

     <para>
      Sometimes, efficient scanning of a large table requires that index
      parameters be provided from more than one other table (commonly,
      dimension tables whose keys are needed to index a large fact table).
      The planner should be able to find such plans, but an overly
      restrictive search heuristic prevented it.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent improper reordering of antijoins (NOT EXISTS joins) versus
      other outer joins (Tom Lane)
     </para>

     <para>
      This oversight in the planner has been observed to cause <quote>could
      not find RelOptInfo for given relids</quote> errors, but it seems possible
      that sometimes an incorrect query plan might get past that consistency
      check and result in silently-wrong query output.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect matching of subexpressions in outer-join plan nodes
      (Tom Lane)
     </para>

     <para>
      Previously, if textually identical non-strict subexpressions were used
      both above and below an outer join, the planner might try to re-use
      the value computed below the join, which would be incorrect because the
      executor would force the value to NULL in case of an unmatched outer row.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix GEQO planner to cope with failure of its join order heuristic
      (Tom Lane)
     </para>

     <para>
      This oversight has been seen to lead to <quote>failed to join all
      relations together</quote> errors in queries involving <literal>LATERAL</literal>,
      and that might happen in other cases as well.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible deadlock at startup
      when <literal>max_prepared_transactions</literal> is too small
      (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Don't archive useless preallocated WAL files after a timeline switch
      (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Recursively <function>fsync()</function> the data directory after a crash
      (Abhijit Menon-Sen, Robert Haas)
     </para>

     <para>
      This ensures consistency if another crash occurs shortly later.  (The
      second crash would have to be a system-level crash, not just a database
      crash, for there to be a problem.)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix autovacuum launcher's possible failure to shut down, if an error
      occurs after it receives SIGTERM (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Cope with unexpected signals in <function>LockBufferForCleanup()</function>
      (Andres Freund)
     </para>

     <para>
      This oversight could result in spurious errors about <quote>multiple
      backends attempting to wait for pincount 1</quote>.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix crash when doing <literal>COPY IN</literal> to a table with check
      constraints that contain whole-row references (Tom Lane)
     </para>

     <para>
      The known failure case only crashes in 9.4 and up, but there is very
      similar code in 9.3 and 9.2, so back-patch those branches as well.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid waiting for WAL flush or synchronous replication during commit of
      a transaction that was read-only so far as the user is concerned
      (Andres Freund)
     </para>

     <para>
      Previously, a delay could occur at commit in transactions that had
      written WAL due to HOT page pruning, leading to undesirable effects
      such as sessions getting stuck at startup if all synchronous replicas
      are down.  Sessions have also been observed to get stuck in catchup
      interrupt processing when using synchronous replication; this will fix
      that problem as well.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix crash when manipulating hash indexes on temporary tables
      (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible failure during hash index bucket split, if other processes
      are modifying the index concurrently (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Check for interrupts while analyzing index expressions (Jeff Janes)
     </para>

     <para>
      <command>ANALYZE</command> executes index expressions many times; if there are
      slow functions in such an expression, it's desirable to be able to
      cancel the <command>ANALYZE</command> before that loop finishes.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure <structfield>tableoid</structfield> of a foreign table is reported
      correctly when a <literal>READ COMMITTED</literal> recheck occurs after
      locking rows in <command>SELECT FOR UPDATE</command>, <command>UPDATE</command>,
      or <command>DELETE</command> (Etsuro Fujita)
     </para>
    </listitem>

    <listitem>
     <para>
      Add the name of the target server to object description strings for
      foreign-server user mappings (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Include the schema name in object identity strings for conversions
      (&Aacute;lvaro Herrera)
     </para>
    </listitem>

    <listitem>
     <para>
      Recommend setting <literal>include_realm</literal> to 1 when using
      Kerberos/GSSAPI/SSPI authentication (Stephen Frost)
     </para>

     <para>
      Without this, identically-named users from different realms cannot be
      distinguished.  For the moment this is only a documentation change, but
      it will become the default setting in <productname>PostgreSQL</productname> 9.5.
     </para>
    </listitem>

    <listitem>
     <para>
      Remove code for matching IPv4 <filename>pg_hba.conf</filename> entries to
      IPv4-in-IPv6 addresses (Tom Lane)
     </para>

     <para>
      This hack was added in 2003 in response to a report that some Linux
      kernels of the time would report IPv4 connections as having
      IPv4-in-IPv6 addresses.  However, the logic was accidentally broken in
      9.0.  The lack of any field complaints since then shows that it's not
      needed anymore.  Now we have reports that the broken code causes
      crashes on some systems, so let's just remove it rather than fix it.
      (Had we chosen to fix it, that would make for a subtle and potentially
      security-sensitive change in the effective meaning of
      IPv4 <filename>pg_hba.conf</filename> entries, which does not seem like a good
      thing to do in minor releases.)
     </para>
    </listitem>

    <listitem>
     <para>
      Report WAL flush, not insert, position in <literal>IDENTIFY_SYSTEM</literal>
      replication command (Heikki Linnakangas)
     </para>

     <para>
      This avoids a possible startup failure
      in <application>pg_receivexlog</application>.
     </para>
    </listitem>

    <listitem>
     <para>
      While shutting down service on Windows, periodically send status
      updates to the Service Control Manager to prevent it from killing the
      service too soon; and ensure that <application>pg_ctl</application> will wait for
      shutdown (Krystian Bigaj)
     </para>
    </listitem>

    <listitem>
     <para>
      Reduce risk of network deadlock when using <application>libpq</application>'s
      non-blocking mode (Heikki Linnakangas)
     </para>

     <para>
      When sending large volumes of data, it's important to drain the input
      buffer every so often, in case the server has sent enough response data
      to cause it to block on output.  (A typical scenario is that the server
      is sending a stream of NOTICE messages during <literal>COPY FROM
      STDIN</literal>.)  This worked properly in the normal blocking mode, but not
      so much in non-blocking mode.  We've modified <application>libpq</application>
      to opportunistically drain input when it can, but a full defense
      against this problem requires application cooperation: the application
      should watch for socket read-ready as well as write-ready conditions,
      and be sure to call <function>PQconsumeInput()</function> upon read-ready.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>libpq</application>, fix misparsing of empty values in URI
      connection strings (Thomas Fanghaenel)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix array handling in <application>ecpg</application> (Michael Meskes)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>psql</application> to sanely handle URIs and conninfo strings as
      the first parameter to <command>\connect</command>
      (David Fetter, Andrew Dunstan, &Aacute;lvaro Herrera)
     </para>

     <para>
      This syntax has been accepted (but undocumented) for a long time, but
      previously some parameters might be taken from the old connection
      instead of the given string, which was agreed to be undesirable.
     </para>
    </listitem>

    <listitem>
     <para>
      Suppress incorrect complaints from <application>psql</application> on some
      platforms that it failed to write <filename>~/.psql_history</filename> at exit
      (Tom Lane)
     </para>

     <para>
      This misbehavior was caused by a workaround for a bug in very old
      (pre-2006) versions of <application>libedit</application>.  We fixed it by
      removing the workaround, which will cause a similar failure to appear
      for anyone still using such versions of <application>libedit</application>.
      Recommendation: upgrade that library, or use <application>libreadline</application>.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dump</application>'s rule for deciding which casts are
      system-provided casts that should not be dumped (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_dump</application>, fix failure to honor <literal>-Z</literal>
      compression level option together with <literal>-Fd</literal>
      (Michael Paquier)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>pg_dump</application> consider foreign key relationships
      between extension configuration tables while choosing dump order
      (Gilles Darold, Michael Paquier, Stephen Frost)
     </para>

     <para>
      This oversight could result in producing dumps that fail to reload
      because foreign key constraints are transiently violated.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid possible <application>pg_dump</application> failure when concurrent sessions
      are creating and dropping temporary functions (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dumping of views that are just <literal>VALUES(...)</literal> but have
      column aliases (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_upgrade</application>, force timeline 1 in the new cluster
      (Bruce Momjian)
     </para>

     <para>
      This change prevents upgrade failures caused by bogus complaints about
      missing WAL history files.
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_upgrade</application>, check for improperly non-connectable
      databases before proceeding
      (Bruce Momjian)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_upgrade</application>, quote directory paths
      properly in the generated <literal>delete_old_cluster</literal> script
      (Bruce Momjian)
     </para>
    </listitem>

    <listitem>
     <para>
      In <application>pg_upgrade</application>, preserve database-level freezing info
      properly
      (Bruce Momjian)
     </para>

     <para>
      This oversight could cause missing-clog-file errors for tables within
      the <literal>postgres</literal> and <literal>template1</literal> databases.
     </para>
    </listitem>

    <listitem>
     <para>
      Run <application>pg_upgrade</application> and <application>pg_resetxlog</application> with
      restricted privileges on Windows, so that they don't fail when run by
      an administrator (Muhammad Asif Naeem)
     </para>
    </listitem>

    <listitem>
     <para>
      Improve handling of <function>readdir()</function> failures when scanning
      directories in <application>initdb</application> and <application>pg_basebackup</application>
      (Marco Nenciarini)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix slow sorting algorithm in <filename>contrib/intarray</filename> (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix compile failure on Sparc V8 machines (Rob Rowan)
     </para>
    </listitem>

    <listitem>
     <para>
      Silence some build warnings on macOS (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2015d
      for DST law changes in Egypt, Mongolia, and Palestine, plus historical
      changes in Canada and Chile.  Also adopt revised zone abbreviations for
      the America/Adak zone (HST/HDT not HAST/HADT).
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-6">
  <title>Release 9.3.6</title>

  <formalpara>
  <title>Release date:</title>
  <para>2015-02-05</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.5.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.6</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you are a Windows user and are using the <quote>Norwegian
    (Bokm&aring;l)</quote> locale, manual action is needed after the upgrade to
    replace any <quote>Norwegian (Bokm&aring;l)_Norway</quote> locale names stored
    in <productname>PostgreSQL</productname> system catalogs with the plain-ASCII
    alias <quote>Norwegian_Norway</quote>.  For details see
    <ulink url="http://wiki.postgresql.org/wiki/Changes_To_Norwegian_Locale"></ulink>
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.5,
    see <xref linkend="release-9-3-5"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master [0150ab567] 2015-02-02 10:00:44 -0500
Branch: REL9_4_STABLE [1628a0bbf] 2015-02-02 10:00:49 -0500
Branch: REL9_3_STABLE [b8b580147] 2015-02-02 10:00:50 -0500
Branch: REL9_2_STABLE [5ae3bf1af] 2015-02-02 10:00:50 -0500
Branch: REL9_1_STABLE [037529a11] 2015-02-02 10:00:51 -0500
Branch: REL9_0_STABLE [611e110aa] 2015-02-02 10:00:52 -0500
Author: Bruce Momjian <bruce@momjian.us>
Branch: master [9241c84cb] 2015-02-02 10:00:45 -0500
Branch: REL9_4_STABLE [56d2bee9d] 2015-02-02 10:00:49 -0500
Branch: REL9_3_STABLE [fe2526990] 2015-02-02 10:00:50 -0500
Branch: REL9_2_STABLE [e09651e9d] 2015-02-02 10:00:50 -0500
Branch: REL9_1_STABLE [2ceb63deb] 2015-02-02 10:00:51 -0500
Branch: REL9_0_STABLE [56b970f2e] 2015-02-02 10:00:52 -0500
-->

    <listitem>
     <para>
      Fix buffer overruns in <function>to_char()</function>
      (Bruce Momjian)
     </para>

     <para>
      When <function>to_char()</function> processes a numeric formatting template
      calling for a large number of digits, <productname>PostgreSQL</productname>
      would read past the end of a buffer.  When processing a crafted
      timestamp formatting template, <productname>PostgreSQL</productname> would write
      past the end of a buffer.  Either case could crash the server.
      We have not ruled out the possibility of attacks that lead to
      privilege escalation, though they seem unlikely.
      (CVE-2015-0241)
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master [29725b3db] 2015-02-02 10:00:45 -0500
Branch: REL9_4_STABLE [2ac95c83c] 2015-02-02 10:00:49 -0500
Branch: REL9_3_STABLE [bc4d5f2e5] 2015-02-02 10:00:50 -0500
Branch: REL9_2_STABLE [c6c6aa288] 2015-02-02 10:00:51 -0500
Branch: REL9_1_STABLE [98f2479d8] 2015-02-02 10:00:51 -0500
Branch: REL9_0_STABLE [9e05c5063] 2015-02-02 10:00:52 -0500
-->

    <listitem>
     <para>
      Fix buffer overrun in replacement <function>*printf()</function> functions
      (Tom Lane)
     </para>

     <para>
      <productname>PostgreSQL</productname> includes a replacement implementation
      of <function>printf</function> and related functions.  This code will overrun
      a stack buffer when formatting a floating point number (conversion
      specifiers <literal>e</literal>, <literal>E</literal>, <literal>f</literal>, <literal>F</literal>,
      <literal>g</literal> or <literal>G</literal>) with requested precision greater than
      about 500.  This will crash the server, and we have not ruled out the
      possibility of attacks that lead to privilege escalation.
      A database user can trigger such a buffer overrun through
      the <function>to_char()</function> SQL function.  While that is the only
      affected core <productname>PostgreSQL</productname> functionality, extension
      modules that use printf-family functions may be at risk as well.
     </para>

     <para>
      This issue primarily affects <productname>PostgreSQL</productname> on Windows.
      <productname>PostgreSQL</productname> uses the system implementation of these
      functions where adequate, which it is on other modern platforms.
      (CVE-2015-0242)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [1dc755158] 2015-02-02 10:00:45 -0500
Branch: REL9_4_STABLE [82806cf4e] 2015-02-02 10:00:49 -0500
Branch: REL9_3_STABLE [6994f0790] 2015-02-02 10:00:50 -0500
Branch: REL9_2_STABLE [d95ebe0ac] 2015-02-02 10:00:51 -0500
Branch: REL9_1_STABLE [11f738a8a] 2015-02-02 10:00:51 -0500
Branch: REL9_0_STABLE [ce6f261cd] 2015-02-02 10:00:52 -0500
Author: Noah Misch <noah@leadboat.com>
Branch: master [8b59672d8] 2015-02-02 10:00:45 -0500
Branch: REL9_4_STABLE [258e294db] 2015-02-02 10:00:49 -0500
Branch: REL9_3_STABLE [a558ad3a7] 2015-02-02 10:00:50 -0500
Branch: REL9_2_STABLE [d1972da8c] 2015-02-02 10:00:51 -0500
Branch: REL9_1_STABLE [8d412e02e] 2015-02-02 10:00:52 -0500
Branch: REL9_0_STABLE [0a3ee8a5f] 2015-02-02 10:00:52 -0500
-->

    <listitem>
     <para>
      Fix buffer overruns in <filename>contrib/pgcrypto</filename>
      (Marko Tiikkaja, Noah Misch)
     </para>

     <para>
      Errors in memory size tracking within the <filename>pgcrypto</filename>
      module permitted stack buffer overruns and improper dependence on the
      contents of uninitialized memory.  The buffer overrun cases can
      crash the server, and we have not ruled out the possibility of
      attacks that lead to privilege escalation.
      (CVE-2015-0243)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [2b3a8b20c] 2015-02-02 17:09:53 +0200
Branch: REL9_4_STABLE [57ec87c6b] 2015-02-02 17:09:46 +0200
Branch: REL9_3_STABLE [cd19848bd] 2015-02-02 17:09:40 +0200
Branch: REL9_2_STABLE [289592b23] 2015-02-02 17:09:35 +0200
Branch: REL9_1_STABLE [af9c5c074] 2015-02-02 17:09:31 +0200
Branch: REL9_0_STABLE [47ba0fbd7] 2015-02-02 17:09:25 +0200
-->

    <listitem>
     <para>
      Fix possible loss of frontend/backend protocol synchronization after
      an error
      (Heikki Linnakangas)
     </para>

     <para>
      If any error occurred while the server was in the middle of reading a
      protocol message from the client, it could lose synchronization and
      incorrectly try to interpret part of the message's data as a new
      protocol message.  An attacker able to submit crafted binary data
      within a command parameter might succeed in injecting his own SQL
      commands this way.  Statement timeout and query cancellation are the
      most likely sources of errors triggering this scenario.  Particularly
      vulnerable are applications that use a timeout and also submit
      arbitrary user-crafted data as binary query parameters.  Disabling
      statement timeout will reduce, but not eliminate, the risk of
      exploit.  Our thanks to Emil Lenngren for reporting this issue.
      (CVE-2015-0244)
     </para>
    </listitem>

<!--
Author: Stephen Frost <sfrost@snowman.net>
Branch: master [804b6b6db] 2015-01-28 12:31:30 -0500
Branch: REL9_4_STABLE [3cc74a3d6] 2015-01-28 12:32:06 -0500
Branch: REL9_3_STABLE [4b9874216] 2015-01-28 12:32:39 -0500
Branch: REL9_2_STABLE [d49f84b08] 2015-01-28 12:32:56 -0500
Branch: REL9_1_STABLE [9406884af] 2015-01-28 12:33:15 -0500
Branch: REL9_0_STABLE [3a2063369] 2015-01-28 12:33:29 -0500
-->

    <listitem>
     <para>
      Fix information leak via constraint-violation error messages
      (Stephen Frost)
     </para>

     <para>
      Some server error messages show the values of columns that violate
      a constraint, such as a unique constraint.  If the user does not have
      <literal>SELECT</literal> privilege on all columns of the table, this could
      mean exposing values that the user should not be able to see.  Adjust
      the code so that values are displayed only when they came from the SQL
      command or could be selected by the user.
      (CVE-2014-8161)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [f6dc6dd5b] 2014-12-17 22:48:40 -0500
Branch: REL9_4_STABLE [6b87d423d] 2014-12-17 22:48:45 -0500
Branch: REL9_3_STABLE [442dc2c35] 2014-12-17 22:48:46 -0500
Branch: REL9_2_STABLE [0046f651d] 2014-12-17 22:48:47 -0500
Branch: REL9_1_STABLE [6aa98e957] 2014-12-17 22:48:47 -0500
Branch: REL9_0_STABLE [6d45ee572] 2014-12-17 22:48:48 -0500
-->

    <listitem>
     <para>
      Lock down regression testing's temporary installations on Windows
      (Noah Misch)
     </para>

     <para>
      Use SSPI authentication to allow connections only from the OS user
      who launched the test suite.  This closes on Windows the same
      vulnerability previously closed on other platforms, namely that other
      users might be able to connect to the test postmaster.
      (CVE-2014-0067)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [8f80dcf3c] 2014-10-24 19:59:49 +0300
Branch: REL9_2_STABLE [d440c4b55] 2014-10-24 19:59:52 +0300
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [2a1b34959] 2014-10-24 19:36:28 +0300
Branch: REL9_2_STABLE [737ae3fc7] 2014-10-24 19:53:27 +0300
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [aa1d2fc5e] 2015-01-16 13:28:19 +0200
Branch: REL9_4_STABLE [2049a7d82] 2015-01-16 13:10:06 +0200
Branch: REL9_3_STABLE [1619442a1] 2015-01-16 13:10:15 +0200
Branch: REL9_2_STABLE [6bf343c6e] 2015-01-16 13:10:23 +0200
-->

    <listitem>
     <para>
      Cope with the Windows locale named <quote>Norwegian (Bokm&aring;l)</quote>
      (Heikki Linnakangas)
     </para>

     <para>
      Non-ASCII locale names are problematic since it's not clear what
      encoding they should be represented in.  Map the troublesome locale
      name to a plain-ASCII alias, <quote>Norwegian_Norway</quote>.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [f88300168] 2014-11-04 13:24:14 -0500
Branch: REL9_2_STABLE [db72ad02e] 2014-11-04 13:24:17 -0500
Branch: REL9_1_STABLE [7c6f55e9e] 2014-11-04 13:24:22 -0500
Branch: REL9_0_STABLE [45a607d5c] 2014-11-04 13:24:26 -0500
-->

    <listitem>
     <para>
      Avoid possible data corruption if <command>ALTER DATABASE SET
      TABLESPACE</command> is used to move a database to a new tablespace and then
      shortly later move it back to its original tablespace (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [81f0a5e38] 2014-10-29 18:12:08 -0400
Branch: REL9_2_STABLE [40058fbce] 2014-10-29 18:12:11 -0400
Branch: REL9_1_STABLE [6ec1c3ef8] 2014-10-29 18:12:17 -0400
Branch: REL9_0_STABLE [9d06da58e] 2014-10-29 18:12:20 -0400
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [e65b550b3] 2014-10-30 13:03:28 -0400
Branch: REL9_2_STABLE [38cb8687a] 2014-10-30 13:03:31 -0400
Branch: REL9_1_STABLE [fcf0246b2] 2014-10-30 13:03:34 -0400
Branch: REL9_0_STABLE [73f950fc8] 2014-10-30 13:03:39 -0400
-->

    <listitem>
     <para>
      Avoid corrupting tables when <command>ANALYZE</command> inside a transaction
      is rolled back (Andres Freund, Tom Lane, Michael Paquier)
     </para>

     <para>
      If the failing transaction had earlier removed the last index, rule, or
      trigger from the table, the table would be left in a corrupted state
      with the relevant <structname>pg_class</structname> flags not set though they
      should be.
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [d7624e562] 2014-10-20 23:45:31 +0200
Branch: REL9_2_STABLE [fd29810d1] 2014-10-20 23:47:00 +0200
Branch: REL9_1_STABLE [d5fef87e9] 2014-10-20 23:47:45 +0200
-->

    <listitem>
     <para>
      Ensure that unlogged tables are copied correctly
      during <command>CREATE DATABASE</command> or <command>ALTER DATABASE SET
      TABLESPACE</command> (Pavan Deolasee, Andres Freund)
     </para>
    </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
Branch: REL9_3_STABLE [e35db342a] 2014-09-22 16:19:59 -0400
-->

    <listitem>
     <para>
      Fix incorrect processing
      of <structname>CreateEventTrigStmt</structname>.<structfield>eventname</structfield> (Petr
      Jelinek)
     </para>

     <para>
      This could result in misbehavior if <command>CREATE EVENT TRIGGER</command>
      were executed as a prepared query, or via extended query protocol.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [2a83e0349] 2014-11-11 17:00:21 -0500
Branch: REL9_2_STABLE [1c2f9a4f6] 2014-11-11 17:00:25 -0500
Branch: REL9_1_STABLE [94d5d57d5] 2014-11-11 17:00:28 -0500
-->

    <listitem>
     <para>
      Fix <command>DROP</command>'s dependency searching to correctly handle the
      case where a table column is recursively visited before its table
      (Petr Jelinek, Tom Lane)
     </para>

     <para>
      This case is only known to arise when an extension creates both a
      datatype and a table using that datatype.  The faulty code might
      refuse a <command>DROP EXTENSION</command> unless <literal>CASCADE</literal> is
      specified, which should not be required.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [c480cb9d2] 2015-01-15 18:52:58 -0500
Branch: REL9_4_STABLE [b75d18bd4] 2015-01-15 18:53:05 -0500
Branch: REL9_3_STABLE [34668c8ec] 2015-01-15 18:52:28 -0500
Branch: REL9_2_STABLE [0acb32efb] 2015-01-15 18:52:31 -0500
Branch: REL9_1_STABLE [450530fce] 2015-01-15 18:52:34 -0500
Branch: REL9_0_STABLE [5308e085b] 2015-01-15 18:52:38 -0500
-->

    <listitem>
     <para>
      Fix use-of-already-freed-memory problem in EvalPlanQual processing
      (Tom Lane)
     </para>

     <para>
      In <literal>READ COMMITTED</literal> mode, queries that lock or update
      recently-updated rows could crash as a result of this bug.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [0e5680f47] 2014-12-26 13:52:27 -0300
Branch: REL9_4_STABLE [0e3a1f71d] 2014-12-26 13:52:27 -0300
Branch: REL9_3_STABLE [048912386] 2014-12-26 13:52:27 -0300
-->

    <listitem>
     <para>
      Avoid possible deadlock while trying to acquire tuple locks
      in EvalPlanQual processing (&Aacute;lvaro Herrera, Mark Kirkwood)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [d5e3d1e96] 2015-01-04 15:48:29 -0300
Branch: REL9_4_STABLE [51742063b] 2015-01-04 15:48:29 -0300
Branch: REL9_3_STABLE [54a8abc2b] 2015-01-04 15:48:29 -0300
-->

    <listitem>
     <para>
      Fix failure to wait when a transaction tries to acquire a <literal>FOR
      NO KEY EXCLUSIVE</literal> tuple lock, while multiple other transactions
      currently hold <literal>FOR SHARE</literal> locks (&Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [2ae8a01ca] 2014-12-11 21:02:31 -0500
Branch: REL9_2_STABLE [cd63c57e5] 2014-12-11 21:02:34 -0500
Branch: REL9_1_STABLE [bca39b578] 2014-12-11 21:02:38 -0500
Branch: REL9_0_STABLE [662eebdc6] 2014-12-11 21:02:41 -0500
-->

    <listitem>
     <para>
      Fix planning of <command>SELECT FOR UPDATE</command> when using a partial
      index on a child table (Kyotaro Horiguchi)
     </para>

     <para>
      In <literal>READ COMMITTED</literal> mode, <command>SELECT FOR UPDATE</command> must
      also recheck the partial index's <literal>WHERE</literal> condition when
      rechecking a recently-updated row to see if it still satisfies the
      query's <literal>WHERE</literal> condition.  This requirement was missed if the
      index belonged to an inheritance child table, so that it was possible
      to incorrectly return rows that no longer satisfy the query condition.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [f14196c35] 2014-12-11 19:37:07 -0500
Branch: REL9_2_STABLE [deadbf4f3] 2014-12-11 19:37:10 -0500
Branch: REL9_1_STABLE [21946ac9b] 2014-12-11 19:37:14 -0500
Branch: REL9_0_STABLE [f5e4e92fb] 2014-12-11 19:37:17 -0500
-->

    <listitem>
     <para>
      Fix corner case wherein <command>SELECT FOR UPDATE</command> could return a row
      twice, and possibly miss returning other rows (Tom Lane)
     </para>

     <para>
      In <literal>READ COMMITTED</literal> mode, a <command>SELECT FOR UPDATE</command>
      that is scanning an inheritance tree could incorrectly return a row
      from a prior child table instead of the one it should return from a
      later child table.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [a5cd70dcb] 2015-01-15 13:18:12 -0500
Branch: REL9_4_STABLE [d25192892] 2015-01-15 13:18:16 -0500
Branch: REL9_3_STABLE [939f0fb67] 2015-01-15 13:18:19 -0500
-->

    <listitem>
     <para>
      Improve performance of <command>EXPLAIN</command> with large range tables
      (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [7a9c8cefb] 2014-08-09 13:46:42 -0400
Branch: REL9_2_STABLE [b4dacab12] 2014-08-09 13:46:45 -0400
Branch: REL9_1_STABLE [bbe826f21] 2014-08-09 13:46:48 -0400
Branch: REL9_0_STABLE [4ff49746e] 2014-08-09 13:46:52 -0400
-->

    <listitem>
     <para>
      Reject duplicate column names in the referenced-columns list of
      a <literal>FOREIGN KEY</literal> declaration (David Rowley)
     </para>

     <para>
      This restriction is per SQL standard.  Previously we did not reject
      the case explicitly, but later on the code would fail with
      bizarre-looking errors.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [6306d0712] 2014-07-22 13:30:14 -0400
-->

    <listitem>
     <para>
      Re-enable error for <literal>SELECT ... OFFSET -1</literal> (Tom Lane)
     </para>

     <para>
      A negative offset value has been an error since 8.4, but an
      optimization added in 9.3 accidentally turned the case into a no-op.
      Restore the expected behavior.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [8b65e0a33] 2014-08-09 18:40:34 -0400
Branch: REL9_2_STABLE [15026ab97] 2014-08-09 18:40:38 -0400
-->

    <listitem>
     <para>
      Restore previous behavior of conversion of domains to JSON
      (Tom Lane)
     </para>

     <para>
      This change causes domains over numeric and boolean to be treated
      like their base types for purposes of conversion to JSON.  It worked
      like that before 9.3.5 and 9.2.9, but was unintentionally changed
      while fixing a related problem.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [8571ecb24] 2014-12-02 15:02:43 -0500
-->

    <listitem>
     <para>
      Fix <function>json_agg()</function> to not return extra trailing right
      brackets in its result (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [25bf13fe1] 2014-09-11 23:30:57 -0400
Branch: REL9_2_STABLE [228ed4370] 2014-09-11 23:31:00 -0400
Branch: REL9_1_STABLE [cf5c20b06] 2014-09-11 23:31:03 -0400
Branch: REL9_0_STABLE [26f8a4691] 2014-09-11 23:31:06 -0400
-->

    <listitem>
     <para>
      Fix bugs in raising a <type>numeric</type> value to a large integral power
      (Tom Lane)
     </para>

     <para>
      The previous code could get a wrong answer, or consume excessive
      amounts of time and memory before realizing that the answer must
      overflow.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [10b81fbdc] 2014-12-01 15:25:08 -0500
Branch: REL9_2_STABLE [e640042e9] 2014-12-01 15:25:12 -0500
Branch: REL9_1_STABLE [2e3cc3955] 2014-12-01 15:25:15 -0500
Branch: REL9_0_STABLE [e6550626c] 2014-12-01 15:25:18 -0500
-->

    <listitem>
     <para>
      In <function>numeric_recv()</function>, truncate away any fractional digits
      that would be hidden according to the value's <literal>dscale</literal> field
      (Tom Lane)
     </para>

     <para>
      A <type>numeric</type> value's display scale (<literal>dscale</literal>) should
      never be less than the number of nonzero fractional digits; but
      apparently there's at least one broken client application that
      transmits binary <type>numeric</type> values in which that's true.
      This leads to strange behavior since the extra digits are taken into
      account by arithmetic operations even though they aren't printed.
      The least risky fix seems to be to truncate away such <quote>hidden</quote>
      digits on receipt, so that the value is indeed what it prints as.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [bbfdf5d75] 2014-09-23 20:25:36 -0400
Branch: REL9_2_STABLE [3359a818c] 2014-09-23 20:25:39 -0400
-->

    <listitem>
     <para>
      Fix incorrect search for shortest-first regular expression matches
      (Tom Lane)
     </para>

     <para>
      Matching would often fail when the number of allowed iterations is
      limited by a <literal>?</literal> quantifier or a bound expression.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [7672bbca0] 2014-07-21 22:41:27 -0400
Branch: REL9_2_STABLE [f54d97c5e] 2014-07-21 22:41:30 -0400
Branch: REL9_1_STABLE [124331b61] 2014-07-21 22:41:33 -0400
Branch: REL9_0_STABLE [6e5a39c9e] 2014-07-21 22:41:36 -0400
-->

    <listitem>
     <para>
      Reject out-of-range numeric timezone specifications (Tom Lane)
     </para>

     <para>
      Simple numeric timezone specifications exceeding +/- 168 hours (one
      week) would be accepted, but could then cause null-pointer dereference
      crashes in certain operations.  There's no use-case for such large UTC
      offsets, so reject them.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [1aa526f3f] 2014-10-27 10:51:29 +0200
Branch: REL9_2_STABLE [604d94d4c] 2014-10-27 10:51:33 +0200
Branch: REL9_1_STABLE [4d1c738d1] 2014-10-27 10:51:36 +0200
Branch: REL9_0_STABLE [10059c2da] 2014-10-27 10:51:38 +0200
-->

    <listitem>
     <para>
      Fix bugs in <type>tsquery</type> <literal>@&gt;</literal> <type>tsquery</type>
      operator (Heikki Linnakangas)
     </para>

     <para>
      Two different terms would be considered to match if they had the same
      CRC.  Also, if the second operand had more terms than the first, it
      would be assumed not to be contained in the first; which is wrong
      since it might contain duplicate terms.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [385f0d98a] 2014-10-23 13:11:34 -0400
Branch: REL9_2_STABLE [f09369da8] 2014-10-23 13:11:37 -0400
Branch: REL9_1_STABLE [94de3a679] 2014-10-23 13:11:41 -0400
Branch: REL9_0_STABLE [21fa26b65] 2014-10-23 13:11:45 -0400
-->

    <listitem>
     <para>
      Improve ispell dictionary's defenses against bad affix files (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [5a74ff373] 2014-11-06 20:52:52 -0500
Branch: REL9_2_STABLE [0bb318595] 2014-11-06 20:52:57 -0500
Branch: REL9_1_STABLE [076688084] 2014-11-06 20:53:02 -0500
Branch: REL9_0_STABLE [39493e4d9] 2014-11-06 20:53:07 -0500
-->

    <listitem>
     <para>
      Allow more than 64K phrases in a thesaurus dictionary (David Boutin)
     </para>

     <para>
      The previous coding could crash on an oversize dictionary, so this was
      deemed a back-patchable bug fix rather than a feature addition.
     </para>
    </listitem>

<!--
Author: Peter Eisentraut <peter_e@gmx.net>
Branch: master [79af9a1d2] 2015-01-06 23:06:13 -0500
Branch: REL9_4_STABLE [6bbf75192] 2015-01-17 22:11:20 -0500
Branch: REL9_3_STABLE [e32cb8d0e] 2015-01-17 22:13:27 -0500
Branch: REL9_2_STABLE [c8ef5b1ac] 2015-01-17 22:14:21 -0500
Branch: REL9_1_STABLE [c975fa471] 2015-01-17 22:37:07 -0500
Branch: REL9_0_STABLE [cebb3f032] 2015-01-17 22:37:32 -0500
-->

    <listitem>
     <para>
      Fix namespace handling in <function>xpath()</function> (Ali Akbar)
     </para>

     <para>
      Previously, the <type>xml</type> value resulting from
      an <function>xpath()</function> call would not have namespace declarations if
      the namespace declarations were attached to an ancestor element in the
      input <type>xml</type> value, rather than to the specific element being
      returned.  Propagate the ancestral declaration so that the result is
      correct when considered in isolation.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [07ab4ec4c] 2014-11-10 15:21:20 -0500
Branch: REL9_2_STABLE [19ccaf9d4] 2014-11-10 15:21:26 -0500
-->

    <listitem>
     <para>
      Ensure that whole-row variables expose nonempty column names
      to functions that pay attention to column names within composite
      arguments (Tom Lane)
     </para>

     <para>
      In some contexts, constructs like <literal>row_to_json(tab.*)</literal> may
      not produce the expected column names.  This is fixed properly as of
      9.4; in older branches, just ensure that we produce some nonempty
      name.  (In some cases this will be the underlying table's column name
      rather than the query-assigned alias that should theoretically be
      visible.)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [c57cdc9c1] 2014-11-22 16:01:12 -0500
Branch: REL9_2_STABLE [906599f65] 2014-11-22 16:01:15 -0500
-->

    <listitem>
     <para>
      Fix mishandling of system columns,
      particularly <structfield>tableoid</structfield>, in FDW queries (Etsuro Fujita)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [3d660d33a] 2015-01-30 12:30:59 -0500
Branch: REL9_4_STABLE [b6a164e5c] 2015-01-30 12:31:08 -0500
Branch: REL9_3_STABLE [527ff8baf] 2015-01-30 12:30:43 -0500
-->

    <listitem>
     <para>
      Fix assorted oversights in range-operator selectivity estimation
      (Emre Hasegeli)
     </para>

     <para>
      This patch fixes corner-case <quote>unexpected operator NNNN</quote> planner
      errors, and improves the selectivity estimates for some other cases.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [f6abf8f08] 2014-10-26 16:12:29 -0400
Branch: REL9_2_STABLE [4586572d7] 2014-10-26 16:12:32 -0400
-->

    <listitem>
     <para>
      Avoid doing <literal><replaceable>indexed_column</replaceable> = ANY
      (<replaceable>array</replaceable>)</literal> as an index qualifier if that leads
      to an inferior plan (Andrew Gierth)
     </para>

     <para>
      In some cases, <literal>= ANY</literal> conditions applied to non-first index
      columns would be done as index conditions even though it would be
      better to use them as simple filter conditions.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [4e54685d0] 2014-10-20 12:23:48 -0400
-->

    <listitem>
     <para>
      Fix <quote>variable not found in subplan target list</quote> planner
      failure when an inline-able SQL function taking a composite argument
      is used in a <literal>LATERAL</literal> subselect and the composite argument
      is a lateral reference (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [b2b95de61] 2014-10-01 19:30:30 -0400
Branch: REL9_2_STABLE [71b88cf52] 2014-10-01 19:30:34 -0400
Branch: REL9_1_STABLE [477023e94] 2014-10-01 19:30:38 -0400
Branch: REL9_0_STABLE [288f15b7c] 2014-10-01 19:30:41 -0400
-->

    <listitem>
     <para>
      Fix planner problems with nested append relations, such as inherited
      tables within <literal>UNION ALL</literal> subqueries (Tom Lane)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [ef8ac584e] 2014-10-03 14:50:29 +0300
Branch: REL9_2_STABLE [8e137b075] 2014-10-03 14:50:40 +0300
Branch: REL9_1_STABLE [f270a1611] 2014-10-03 14:50:46 +0300
Branch: REL9_0_STABLE [f04b112d5] 2014-10-03 14:50:58 +0300
-->

    <listitem>
     <para>
      Fail cleanly when a GiST index tuple doesn't fit on a page, rather
      than going into infinite recursion (Andrew Gierth)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: REL9_3_STABLE [67ed9d531] 2014-10-03 13:01:27 -0300
Branch: REL9_2_STABLE [769d6815e] 2014-10-03 13:01:27 -0300
Branch: REL9_1_STABLE [06646f52e] 2014-10-03 13:01:27 -0300
Branch: REL9_0_STABLE [50a757698] 2014-10-03 13:01:27 -0300
-->

    <listitem>
     <para>
      Exempt tables that have per-table <varname>cost_limit</varname>
      and/or <varname>cost_delay</varname> settings from autovacuum's global cost
      balancing rules (&Aacute;lvaro Herrera)
     </para>

     <para>
      The previous behavior resulted in basically ignoring these per-table
      settings, which was unintended.  Now, a table having such settings
      will be vacuumed using those settings, independently of what is going
      on in other autovacuum workers.  This may result in heavier total I/O
      load than before, so such settings should be re-examined for sanity.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [4cbecdaaa] 2014-07-30 14:41:49 -0400
Branch: REL9_2_STABLE [c83aed34b] 2014-07-30 14:41:53 -0400
Branch: REL9_1_STABLE [f21afe421] 2014-07-30 14:41:58 -0400
Branch: REL9_0_STABLE [91b4a881c] 2014-07-30 14:42:12 -0400
-->

    <listitem>
     <para>
      Avoid wholesale autovacuuming when autovacuum is nominally off
      (Tom Lane)
     </para>

     <para>
      Even when autovacuum is nominally off, we will still launch autovacuum
      worker processes to vacuum tables that are at risk of XID wraparound.
      However, such a worker process then proceeded to vacuum all tables in
      the target database, if they met the usual thresholds for
      autovacuuming.  This is at best pretty unexpected; at worst it delays
      response to the wraparound threat.  Fix it so that if autovacuum is
      turned off, workers <emphasis>only</emphasis> do anti-wraparound vacuums and
      not any other work.
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [2c3ebfd1a] 2014-11-15 01:21:07 +0100
Branch: REL9_2_STABLE [ea8b3833e] 2014-11-15 01:21:45 +0100
Branch: REL9_1_STABLE [d85b646d0] 2014-11-15 01:22:32 +0100
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [672b43e68] 2014-11-15 01:21:02 +0100
Branch: REL9_2_STABLE [c5baa708f] 2014-11-15 01:21:40 +0100
Branch: REL9_1_STABLE [fde9994bc] 2014-11-15 01:22:32 +0100
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [c7299d32f] 2014-11-15 01:20:29 +0100
Branch: REL9_2_STABLE [86673a44a] 2014-11-15 01:21:30 +0100
Branch: REL9_1_STABLE [b0a48e996] 2014-11-15 01:22:32 +0100
-->

    <listitem>
     <para>
      During crash recovery, ensure that unlogged relations are rewritten as
      empty and are synced to disk before recovery is considered complete
      (Abhijit Menon-Sen, Andres Freund)
     </para>

     <para>
      This prevents scenarios in which unlogged relations might contain
      garbage data following database crash recovery.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [861d3aa43] 2014-11-13 20:01:55 +0200
Branch: REL9_2_STABLE [7eab804c2] 2014-11-13 20:01:18 +0200
Branch: REL9_1_STABLE [5f1d931cf] 2014-11-13 20:01:09 +0200
Branch: REL9_0_STABLE [681dbe7d4] 2014-11-13 20:00:51 +0200
-->

    <listitem>
     <para>
      Fix race condition between hot standby queries and replaying a
      full-page image (Heikki Linnakangas)
     </para>

     <para>
      This mistake could result in transient errors in queries being
      executed in hot standby.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [a2a718b22] 2014-07-29 11:57:52 +0300
Branch: REL9_2_STABLE [1578d13dc] 2014-07-29 11:58:01 +0300
Branch: REL9_1_STABLE [de88ec6bf] 2014-07-29 11:58:09 +0300
Branch: REL9_0_STABLE [804983961] 2014-07-29 11:58:17 +0300
-->

    <listitem>
     <para>
      Fix several cases where recovery logic improperly ignored WAL records
      for <literal>COMMIT/ABORT PREPARED</literal> (Heikki Linnakangas)
     </para>

     <para>
      The most notable oversight was
      that <varname>recovery_target_xid</varname> could not be used to stop at
      a two-phase commit.
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: REL9_3_STABLE [d45cd9e19] 2014-10-23 16:22:46 +0900
Branch: REL9_2_STABLE [f904e9afd] 2014-10-23 16:31:44 +0900
-->

    <listitem>
     <para>
      Prevent latest WAL file from being archived a second time at completion
      of crash recovery (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: REL9_3_STABLE [3a3b7e316] 2014-11-06 21:25:18 +0900
Branch: REL9_2_STABLE [38eb5d9e8] 2014-11-06 21:25:45 +0900
Branch: REL9_1_STABLE [4e7468074] 2014-11-06 21:26:15 +0900
Branch: REL9_0_STABLE [83c7bfb9a] 2014-11-06 21:26:21 +0900
-->

    <listitem>
     <para>
      Avoid creating unnecessary <filename>.ready</filename> marker files for
      timeline history files (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: REL9_3_STABLE [52eed3d42] 2014-09-05 02:19:29 +0900
Branch: REL9_2_STABLE [78b1228ef] 2014-09-05 02:19:45 +0900
Branch: REL9_1_STABLE [81bffe63c] 2014-09-05 02:19:50 +0900
Branch: REL9_0_STABLE [857a5d6b5] 2014-09-05 02:19:57 +0900
-->

    <listitem>
     <para>
      Fix possible null pointer dereference when an empty prepared statement
      is used and the <varname>log_statement</varname> setting is <literal>mod</literal>
      or <literal>ddl</literal> (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [75b48e1ff] 2015-01-19 23:01:33 -0500
Branch: REL9_4_STABLE [3387cbbcb] 2015-01-19 23:01:36 -0500
Branch: REL9_3_STABLE [19794e997] 2015-01-19 23:01:39 -0500
Branch: REL9_2_STABLE [33b723538] 2015-01-19 23:01:41 -0500
Branch: REL9_1_STABLE [b87c1dcef] 2015-01-19 23:01:44 -0500
Branch: REL9_0_STABLE [a1a8d0249] 2015-01-19 23:01:46 -0500
-->

    <listitem>
     <para>
      Change <quote>pgstat wait timeout</quote> warning message to be LOG level,
      and rephrase it to be more understandable (Tom Lane)
     </para>

     <para>
      This message was originally thought to be essentially a can't-happen
      case, but it occurs often enough on our slower buildfarm members to be
      a nuisance.  Reduce it to LOG level, and expend a bit more effort on
      the wording: it now reads <quote>using stale statistics instead of
      current ones because stats collector is not responding</quote>.
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [cbd9619ac] 2014-10-01 14:34:06 +0200
-->

    <listitem>
     <para>
      Fix possible corruption of postmaster's list of dynamic background
      workers (Andres Freund)
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [27ef6b653] 2014-09-09 23:37:33 +0200
Branch: REL9_2_STABLE [d0b7ffc0f] 2014-09-09 23:37:50 +0200
Branch: REL9_1_STABLE [5af508f66] 2014-09-09 23:45:07 +0200
Branch: REL9_0_STABLE [f25e89601] 2014-09-09 23:48:03 +0200
-->

    <listitem>
     <para>
      Fix SPARC spinlock implementation to ensure correctness if the CPU is
      being run in a non-TSO coherency mode, as some non-Solaris kernels do
      (Andres Freund)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [894459e59] 2015-01-07 22:35:44 -0500
Branch: REL9_4_STABLE [83fb1ca5c] 2015-01-07 22:36:35 -0500
Branch: REL9_3_STABLE [1a366d51e] 2015-01-07 22:40:40 -0500
Branch: REL9_2_STABLE [5ca4e444c] 2015-01-07 22:41:49 -0500
Branch: REL9_1_STABLE [8dc83104e] 2015-01-07 22:42:42 -0500
Branch: REL9_0_STABLE [2e4946169] 2015-01-07 22:46:20 -0500
-->

    <listitem>
     <para>
      Warn if macOS's <function>setlocale()</function> starts an unwanted extra
      thread inside the postmaster (Noah Misch)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [08cd4d9a6] 2014-11-25 17:39:00 +0200
Branch: REL9_2_STABLE [9b468bcec] 2014-11-25 17:39:04 +0200
Branch: REL9_1_STABLE [95be34362] 2014-11-25 17:39:07 +0200
Branch: REL9_0_STABLE [9880fea4f] 2014-11-25 17:39:09 +0200
-->

    <listitem>
     <para>
      Fix processing of repeated <literal>dbname</literal> parameters
      in <function>PQconnectdbParams()</function> (Alex Shulgin)
     </para>

     <para>
      Unexpected behavior ensued if the first occurrence
      of <literal>dbname</literal> contained a connection string or URI to be
      expanded.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [52ef33f72] 2014-10-22 18:41:51 -0400
Branch: REL9_2_STABLE [6fa31d8d1] 2014-10-22 18:41:54 -0400
Branch: REL9_1_STABLE [98144378c] 2014-10-22 18:41:57 -0400
Branch: REL9_0_STABLE [ac6e87537] 2014-10-22 18:42:01 -0400
-->

    <listitem>
     <para>
      Ensure that <application>libpq</application> reports a suitable error message on
      unexpected socket EOF (Marko Tiikkaja, Tom Lane)
     </para>

     <para>
      Depending on kernel behavior, <application>libpq</application> might return an
      empty error string rather than something useful when the server
      unexpectedly closed the socket.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [1325b239b] 2014-10-29 14:40:47 +0200
Branch: REL9_2_STABLE [1a27fbd07] 2014-10-29 14:39:10 +0200
Branch: REL9_1_STABLE [8f7bd8e91] 2014-10-29 14:36:19 +0200
Branch: REL9_0_STABLE [49ef4eba2] 2014-10-29 14:35:39 +0200
-->

    <listitem>
     <para>
      Clear any old error message during <function>PQreset()</function>
      (Heikki Linnakangas)
     </para>

     <para>
      If <function>PQreset()</function> is called repeatedly, and the connection
      cannot be re-established, error messages from the failed connection
      attempts kept accumulating in the <structname>PGconn</structname>'s error
      string.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [d3b162a3d] 2014-11-25 14:10:29 +0200
Branch: REL9_2_STABLE [abcab2a64] 2014-11-25 14:10:43 +0200
Branch: REL9_1_STABLE [5053ad206] 2014-11-25 14:10:48 +0200
Branch: REL9_0_STABLE [1f3517039] 2014-11-25 14:10:54 +0200
-->

    <listitem>
     <para>
      Properly handle out-of-memory conditions while parsing connection
      options in <application>libpq</application> (Alex Shulgin, Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [d3cfe20c6] 2014-10-06 21:23:35 -0400
Branch: REL9_2_STABLE [b513205bc] 2014-10-06 21:23:39 -0400
Branch: REL9_1_STABLE [037b912ec] 2014-10-06 21:23:45 -0400
Branch: REL9_0_STABLE [d9a1e9de5] 2014-10-06 21:23:50 -0400
-->

    <listitem>
     <para>
      Fix array overrun in <application>ecpg</application>'s version
      of <function>ParseDateTime()</function> (Michael Paquier)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [2df66f01a] 2014-12-05 14:31:51 +0200
Branch: REL9_2_STABLE [2b53d583d] 2014-12-05 14:31:45 +0200
Branch: REL9_1_STABLE [729202754] 2014-12-05 14:31:37 +0200
Branch: REL9_0_STABLE [d67be559e] 2014-12-05 14:30:55 +0200
-->

    <listitem>
     <para>
      In <application>initdb</application>, give a clearer error message if a password
      file is specified but is empty (Mats Erik Andersson)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [b0fd5c552] 2014-09-08 16:09:52 -0400
Branch: REL9_2_STABLE [886b58b47] 2014-09-08 16:09:56 -0400
Branch: REL9_1_STABLE [440fcc568] 2014-09-08 16:10:01 -0400
Branch: REL9_0_STABLE [44c518328] 2014-09-08 16:10:05 -0400
-->

    <listitem>
     <para>
      Fix <application>psql</application>'s <command>\s</command> command to work nicely with
      libedit, and add pager support (Stepan Rutz, Tom Lane)
     </para>

     <para>
      When using libedit rather than readline, <command>\s</command> printed the
      command history in a fairly unreadable encoded format, and on recent
      libedit versions might fail altogether.  Fix that by printing the
      history ourselves rather than having the library do it.  A pleasant
      side-effect is that the pager is used if appropriate.
     </para>

     <para>
      This patch also fixes a bug that caused newline encoding to be applied
      inconsistently when saving the command history with libedit.
      Multiline history entries written by older <application>psql</application>
      versions will be read cleanly with this patch, but perhaps not
      vice versa, depending on the exact libedit versions involved.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [28551797a] 2014-12-31 12:18:50 -0500
Branch: REL9_4_STABLE [c35249939] 2014-12-31 12:16:57 -0500
Branch: REL9_3_STABLE [7582cce56] 2014-12-31 12:17:00 -0500
Branch: REL9_2_STABLE [64c506535] 2014-12-31 12:17:04 -0500
Branch: REL9_1_STABLE [1773e0702] 2014-12-31 12:17:08 -0500
Branch: REL9_0_STABLE [2600e4436] 2014-12-31 12:17:12 -0500
-->

    <listitem>
     <para>
      Improve consistency of parsing of <application>psql</application>'s special
      variables (Tom Lane)
     </para>

     <para>
      Allow variant spellings of <literal>on</literal> and <literal>off</literal> (such
      as <literal>1</literal>/<literal>0</literal>) for <literal>ECHO_HIDDEN</literal>
      and <literal>ON_ERROR_ROLLBACK</literal>.  Report a warning for unrecognized
      values for <literal>COMP_KEYWORD_CASE</literal>, <literal>ECHO</literal>,
      <literal>ECHO_HIDDEN</literal>, <literal>HISTCONTROL</literal>,
      <literal>ON_ERROR_ROLLBACK</literal>, and <literal>VERBOSITY</literal>.  Recognize
      all values for all these variables case-insensitively; previously
      there was a mishmash of case-sensitive and case-insensitive behaviors.
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: REL9_3_STABLE [4b1953079] 2014-11-28 02:44:40 +0900
-->

    <listitem>
     <para>
      Make <application>psql</application>'s <command>\watch</command> command display
      nulls as specified by <command>\pset null</command> (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Stephen Frost <sfrost@snowman.net>
Branch: REL9_3_STABLE [7ec399094] 2014-09-12 11:24:28 -0400
Branch: REL9_2_STABLE [5d63f2159] 2014-09-12 11:24:32 -0400
Branch: REL9_1_STABLE [4d96e93cb] 2014-09-12 11:24:36 -0400
Branch: REL9_0_STABLE [1f89fc218] 2014-09-12 11:24:39 -0400
-->

    <listitem>
     <para>
      Fix <application>psql</application>'s expanded-mode display to work
      consistently when using <literal>border</literal> = 3
      and <literal>linestyle</literal> = <literal>ascii</literal> or <literal>unicode</literal>
      (Stephen Frost)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [adfc157dd] 2015-01-05 19:27:04 -0500
Branch: REL9_4_STABLE [c99e41f68] 2015-01-05 19:27:06 -0500
Branch: REL9_3_STABLE [bb1e2426b] 2015-01-05 19:27:09 -0500
-->

    <listitem>
     <para>
      Fix <application>pg_dump</application> to handle comments on event triggers
      without failing (Tom Lane)
     </para>
    </listitem>

<!--
Author: Kevin Grittner <kgrittn@postgresql.org>
Branch: master [cff1bd2a3] 2015-01-30 08:57:24 -0600
Branch: REL9_4_STABLE [cb0168528] 2015-01-30 08:57:53 -0600
Branch: REL9_3_STABLE [cc609c46f] 2015-01-30 09:01:36 -0600
-->

    <listitem>
     <para>
      Allow parallel <application>pg_dump</application> to
      use <option>--serializable-deferrable</option> (Kevin Grittner)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [51fc61334] 2014-07-25 19:48:48 -0400
Branch: REL9_2_STABLE [a6c567437] 2014-07-25 19:48:51 -0400
Branch: REL9_1_STABLE [40c333c39] 2014-07-25 19:48:54 -0400
-->

    <listitem>
     <para>
      Improve performance of <application>pg_dump</application> when the database
      contains many instances of multiple dependency paths between the same
      two objects (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [9fc887121] 2014-11-13 18:19:32 -0500
Branch: REL9_2_STABLE [3c5ce5102] 2014-11-13 18:19:35 -0500
-->

    <listitem>
     <para>
      Fix <application>pg_dumpall</application> to restore its ability to dump from
      pre-8.1 servers (Gilles Darold)
     </para>
    </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
Branch: REL9_3_STABLE [d72ecc91c] 2014-09-26 11:23:43 -0400
Branch: REL9_2_STABLE [a97c8c393] 2014-09-26 11:25:57 -0400
Branch: REL9_1_STABLE [d1844c21b] 2014-09-26 11:36:25 -0400
Branch: REL9_0_STABLE [bbe3c069a] 2014-09-26 11:43:56 -0400
-->

    <listitem>
     <para>
      Fix possible deadlock during parallel restore of a schema-only dump
      (Robert Haas, Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [9a540c1ef] 2014-10-17 12:49:06 -0400
Branch: REL9_2_STABLE [787e20bd4] 2014-10-17 12:49:09 -0400
Branch: REL9_1_STABLE [0c9391e52] 2014-10-17 12:49:11 -0400
Branch: REL9_0_STABLE [31021e7ba] 2014-10-17 12:49:15 -0400
-->

    <listitem>
     <para>
      Fix core dump in <literal>pg_dump --binary-upgrade</literal> on zero-column
      composite type (Rushabh Lathia)
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: REL9_3_STABLE [26a4e0ed7] 2014-11-15 01:21:11 +0100
-->

    <listitem>
     <para>
      Fix failure to fsync tables in nondefault tablespaces
      during <application>pg_upgrade</application> (Abhijit Menon-Sen, Andres Freund)
     </para>

     <para>
      With an operating system crash and some bad luck, this could result in
      data loss during an upgrade.
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: REL9_3_STABLE [fca9f349b] 2014-08-07 14:56:13 -0400
-->

    <listitem>
     <para>
      In <application>pg_upgrade</application>, cope with cases where the new cluster
      creates a TOAST table for a table that didn't previously have one
      (Bruce Momjian)
     </para>

     <para>
      Previously this could result in failures due to OID conflicts.
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: REL9_3_STABLE [24ae44914] 2014-08-04 11:45:45 -0400
-->

    <listitem>
     <para>
      In <application>pg_upgrade</application>, don't try to
      set <literal>autovacuum_multixact_freeze_max_age</literal> for the old cluster
      (Bruce Momjian)
     </para>

     <para>
      This could result in failure because not all 9.3.X versions have that
      parameter.  Fortunately, we don't actually need to set it at all.
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: REL9_3_STABLE [5724f491d] 2014-09-11 18:39:46 -0400
-->

    <listitem>
     <para>
      In <application>pg_upgrade</application>, preserve the transaction ID epoch
      (Bruce Momjian)
     </para>

     <para>
      This oversight did not bother <productname>PostgreSQL</productname> proper,
      but could confuse some external replication tools.
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: master [2c0a48589] 2015-01-03 20:54:12 +0100
Branch: REL9_4_STABLE [90e4a2bf9] 2015-01-03 20:54:13 +0100
Branch: REL9_3_STABLE [f6cea4502] 2015-01-03 20:54:13 +0100
Branch: REL9_2_STABLE [f961ad479] 2015-01-03 20:54:13 +0100
Branch: REL9_1_STABLE [2a0bfa4d6] 2015-01-03 20:54:13 +0100
-->

    <listitem>
     <para>
      Prevent WAL files created by <literal>pg_basebackup -x/-X</literal> from
      being archived again when the standby is promoted (Andres Freund)
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: REL9_3_STABLE [9747a9898] 2014-08-02 15:19:45 +0900
-->

    <listitem>
     <para>
      Fix memory leak in <application>pg_receivexlog</application> (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: REL9_3_STABLE [39217ce41] 2014-08-02 14:59:10 +0900
-->

    <listitem>
     <para>
      Fix unintended suppression of <application>pg_receivexlog</application> verbose
      messages (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [9474c9d81] 2014-09-19 13:19:02 -0400
Branch: REL9_2_STABLE [5ff8c2d7d] 2014-09-19 13:19:05 -0400
-->

    <listitem>
     <para>
      Fix failure of <filename>contrib/auto_explain</filename> to print per-node
      timing information when doing <command>EXPLAIN ANALYZE</command> (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [0ad403c98] 2014-08-28 18:21:14 -0400
Branch: REL9_2_STABLE [f3998521f] 2014-08-28 18:21:17 -0400
Branch: REL9_1_STABLE [9807c8220] 2014-08-28 18:21:20 -0400
-->

    <listitem>
     <para>
      Fix upgrade-from-unpackaged script for <filename>contrib/citext</filename>
      (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [f44290b7b] 2014-11-04 16:54:59 -0500
-->

    <listitem>
     <para>
      Avoid integer overflow and buffer overrun
      in <filename>contrib/hstore</filename>'s <function>hstore_to_json()</function>
      (Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
Branch: REL9_3_STABLE [55c880797] 2014-12-01 11:44:48 -0500
-->

    <listitem>
     <para>
      Fix recognition of numbers in <function>hstore_to_json_loose()</function>,
      so that JSON numbers and strings are correctly distinguished
      (Andrew Dunstan)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [f59c8eff7] 2014-07-22 11:45:53 -0400
Branch: REL9_2_STABLE [810f0d2a2] 2014-07-22 11:45:57 -0400
Branch: REL9_1_STABLE [3c5232ae8] 2014-07-22 11:46:00 -0400
Branch: REL9_0_STABLE [9dc2a3fd0] 2014-07-22 11:46:04 -0400
-->

    <listitem>
     <para>
      Fix block number checking
      in <filename>contrib/pageinspect</filename>'s <function>get_raw_page()</function>
      (Tom Lane)
     </para>

     <para>
      The incorrect checking logic could prevent access to some pages in
      non-main relation forks.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [419de696a] 2014-11-11 17:22:38 -0500
Branch: REL9_2_STABLE [4a9710e6e] 2014-11-11 17:22:44 -0500
Branch: REL9_1_STABLE [4ddd9e72f] 2014-11-11 17:22:51 -0500
Branch: REL9_0_STABLE [ef5a3b957] 2014-11-11 17:22:58 -0500
-->

    <listitem>
     <para>
      Fix <filename>contrib/pgcrypto</filename>'s <function>pgp_sym_decrypt()</function>
      to not fail on messages whose length is 6 less than a power of 2
      (Marko Tiikkaja)
     </para>
    </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
Branch: REL9_3_STABLE [8cf825974] 2014-11-19 12:14:22 -0500
Branch: REL9_2_STABLE [57ce74661] 2014-11-19 12:20:47 -0500
Branch: REL9_1_STABLE [a855c90a7] 2014-11-19 12:26:06 -0500
-->

    <listitem>
     <para>
      Fix file descriptor leak in <filename>contrib/pg_test_fsync</filename>
      (Jeff Janes)
     </para>

     <para>
      This could cause failure to remove temporary files on Windows.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [37507962c] 2015-01-29 20:18:33 -0500
Branch: REL9_4_STABLE [202621d04] 2015-01-29 20:18:37 -0500
Branch: REL9_3_STABLE [53ae24692] 2015-01-29 20:18:40 -0500
Branch: REL9_2_STABLE [66cc74680] 2015-01-29 20:18:42 -0500
Branch: REL9_1_STABLE [290c2daad] 2015-01-29 20:18:44 -0500
Branch: REL9_0_STABLE [dc9a506e6] 2015-01-29 20:18:46 -0500
-->

    <listitem>
     <para>
      Handle unexpected query results, especially NULLs, safely in
      <filename>contrib/tablefunc</filename>'s <function>connectby()</function>
      (Michael Paquier)
     </para>

     <para>
      <function>connectby()</function> previously crashed if it encountered a NULL
      key value.  It now prints that row but doesn't recurse further.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [c393847a1] 2014-11-27 11:12:51 -0500
Branch: REL9_2_STABLE [a1cd04cd0] 2014-11-27 11:12:55 -0500
Branch: REL9_1_STABLE [168636a99] 2014-11-27 11:12:59 -0500
Branch: REL9_0_STABLE [6a694bbab] 2014-11-27 11:13:03 -0500
-->

    <listitem>
     <para>
      Avoid a possible crash in <filename>contrib/xml2</filename>'s
      <function>xslt_process()</function> (Mark Simonetti)
     </para>

     <para>
      <application>libxslt</application> seems to have an undocumented dependency on
      the order in which resources are freed; reorder our calls to avoid a
      crash.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [0247935c7] 2014-11-05 11:34:19 -0500
Branch: REL9_2_STABLE [0ef754cad] 2014-11-05 11:34:22 -0500
Branch: REL9_1_STABLE [7225abf00] 2014-11-05 11:34:25 -0500
-->

    <listitem>
     <para>
      Mark some <filename>contrib</filename> I/O functions with correct volatility
      properties (Tom Lane)
     </para>

     <para>
      The previous over-conservative marking was immaterial in normal use,
      but could cause optimization problems or rejection of valid index
      expression definitions.  Since the consequences are not large, we've
      just adjusted the function definitions in the extension modules'
      scripts, without changing version numbers.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [a59ee8819] 2015-01-30 13:05:30 -0500
Branch: REL9_4_STABLE [70da7aeba] 2015-01-30 13:04:59 -0500
Branch: REL9_3_STABLE [f08cf8ad9] 2015-01-30 13:05:01 -0500
Branch: REL9_2_STABLE [a97dfdfd9] 2015-01-30 13:05:04 -0500
Branch: REL9_1_STABLE [8f51c432c] 2015-01-30 13:05:07 -0500
Branch: REL9_0_STABLE [7c41a32b3] 2015-01-30 13:05:09 -0500
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [8824bae87] 2014-11-18 13:28:13 -0500
Author: Robert Haas <rhaas@postgresql.org>
Branch: master [0b49642b9] 2015-01-15 09:26:03 -0500
Branch: REL9_4_STABLE [7b65f194e] 2015-01-15 09:29:41 -0500
Branch: REL9_3_STABLE [ebbef4f39] 2015-01-15 09:29:55 -0500
Branch: REL9_2_STABLE [d452bfd1b] 2015-01-15 09:42:21 -0500
Branch: REL9_1_STABLE [151fb75b0] 2015-01-15 09:42:33 -0500
Branch: REL9_0_STABLE [0a67c0018] 2015-01-15 09:42:47 -0500
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [e37d474f9] 2015-01-13 14:33:05 +0200
Branch: REL9_4_STABLE [4ebb3494e] 2015-01-13 16:01:04 +0200
Author: Andres Freund <andres@anarazel.de>
Branch: master [8cadeb792] 2015-01-04 15:44:49 +0100
Branch: REL9_4_STABLE [7ced1b6c5] 2015-01-04 15:52:52 +0100
Branch: REL9_3_STABLE [a68b8aec7] 2015-01-04 15:53:08 +0100
Branch: REL9_2_STABLE [6f9b84a40] 2015-01-04 15:55:00 +0100
Author: Andres Freund <andres@anarazel.de>
Branch: master [58bc4747b] 2015-01-04 15:35:46 +0100
Branch: REL9_4_STABLE [2d8411a0a] 2015-01-04 15:35:46 +0100
Branch: REL9_3_STABLE [d33f36f16] 2015-01-04 15:35:47 +0100
Branch: REL9_2_STABLE [029e41afd] 2015-01-04 15:35:47 +0100
Branch: REL9_1_STABLE [39cdf365a] 2015-01-04 15:35:47 +0100
Branch: REL9_0_STABLE [17797e18d] 2015-01-04 15:35:48 +0100
Author: Andres Freund <andres@anarazel.de>
Branch: master [0398ece4c] 2015-01-04 14:36:21 +0100
Branch: REL9_4_STABLE [ff7d46b85] 2015-01-04 14:36:21 +0100
Branch: REL9_3_STABLE [ec14f1601] 2015-01-04 14:36:22 +0100
Branch: REL9_2_STABLE [f4060db11] 2015-01-04 14:36:22 +0100
Author: Tatsuo Ishii <ishii@postgresql.org>
Branch: master [3b5a89c48] 2014-12-30 20:33:01 +0900
Branch: REL9_4_STABLE [458e8bc65] 2014-12-30 20:27:26 +0900
Branch: REL9_3_STABLE [ed0e03283] 2014-12-30 20:20:56 +0900
Branch: REL9_2_STABLE [4db7eaae0] 2014-12-30 19:59:26 +0900
Branch: REL9_1_STABLE [4c136b0b6] 2014-12-30 19:48:53 +0900
Branch: REL9_0_STABLE [9b74f3574] 2014-12-30 19:37:55 +0900
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [66709133c] 2014-12-16 15:35:33 -0500
Branch: REL9_4_STABLE [383d224a0] 2014-12-16 15:35:36 -0500
Branch: REL9_3_STABLE [53960e7eb] 2014-12-16 15:35:40 -0500
Branch: REL9_2_STABLE [e92c67ddc] 2014-12-16 15:35:43 -0500
Branch: REL9_1_STABLE [5c784d96a] 2014-12-16 15:35:46 -0500
Branch: REL9_0_STABLE [a2969bd72] 2014-12-16 15:35:49 -0500
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [d38e8d30c] 2014-12-16 13:31:42 -0500
Branch: REL9_4_STABLE [6c75384ee] 2014-12-16 13:31:57 -0500
Branch: REL9_3_STABLE [3b750ec15] 2014-12-16 13:32:02 -0500
Branch: REL9_2_STABLE [5b2c8f04a] 2014-12-16 13:32:15 -0500
Branch: REL9_1_STABLE [926da211a] 2014-12-16 13:32:25 -0500
Branch: REL9_0_STABLE [961df1853] 2014-12-16 13:32:38 -0500
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [586dd5d6a] 2015-01-24 13:05:42 -0500
Branch: REL9_4_STABLE [d51d4ff31] 2015-01-24 13:05:45 -0500
Branch: REL9_3_STABLE [7240f9200] 2015-01-24 13:05:49 -0500
Branch: REL9_2_STABLE [502e5f9c3] 2015-01-24 13:05:53 -0500
Branch: REL9_1_STABLE [b00a08859] 2015-01-24 13:05:56 -0500
Branch: REL9_0_STABLE [3a3ee655c] 2015-01-24 13:05:58 -0500
-->

    <listitem>
     <para>
      Numerous cleanups of warnings from Coverity static code analyzer
      (Andres Freund, Tatsuo Ishii, Marko Kreen, Tom Lane, Michael Paquier)
     </para>

     <para>
      These changes are mostly cosmetic but in some cases fix corner-case
      bugs, for example a crash rather than a proper error report after an
      out-of-memory failure.  None are believed to represent security
      issues.
     </para>
    </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
Branch: REL9_3_STABLE [05c0059b3] 2014-07-30 12:10:20 -0400
-->

    <listitem>
     <para>
      Fix setup of background workers in EXEC_BACKEND builds, eg Windows
      (Robert Haas)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: REL9_3_STABLE [07115248f] 2014-07-22 11:01:41 -0400
Branch: REL9_2_STABLE [cec0c2182] 2014-07-22 11:01:51 -0400
Branch: REL9_1_STABLE [81af4185a] 2014-07-22 11:02:00 -0400
Branch: REL9_0_STABLE [4c6d0abde] 2014-07-22 11:02:25 -0400
-->

    <listitem>
     <para>
      Detect incompatible OpenLDAP versions during build (Noah Misch)
     </para>

     <para>
      With OpenLDAP versions 2.4.24 through 2.4.31,
      inclusive, <productname>PostgreSQL</productname> backends can crash at exit.
      Raise a warning during <application>configure</application> based on the
      compile-time OpenLDAP version number, and test the crashing scenario
      in the <filename>contrib/dblink</filename> regression test.
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: REL9_3_STABLE [318fe2321] 2014-08-18 23:01:04 -0400
Branch: REL9_2_STABLE [ebd4d9cdd] 2014-08-18 23:01:09 -0400
Branch: REL9_1_STABLE [ba72fc054] 2014-08-18 23:01:13 -0400
Branch: REL9_0_STABLE [e6841c4d6] 2014-08-18 23:01:23 -0400
-->

    <listitem>
     <para>
      In non-MSVC Windows builds, ensure <filename>libpq.dll</filename> is installed
      with execute permissions (Noah Misch)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [aa719391d] 2015-01-19 23:44:19 -0500
Branch: REL9_4_STABLE [3de9f22ac] 2015-01-19 23:44:22 -0500
Branch: REL9_3_STABLE [1681e2f74] 2015-01-19 23:44:24 -0500
Branch: REL9_2_STABLE [89b6a19e1] 2015-01-19 23:44:28 -0500
Branch: REL9_1_STABLE [f4f522deb] 2015-01-19 23:44:30 -0500
Branch: REL9_0_STABLE [338ff75fc] 2015-01-19 23:44:33 -0500
-->

    <listitem>
     <para>
      Make <application>pg_regress</application> remove any temporary installation it
      created upon successful exit (Tom Lane)
     </para>

     <para>
      This results in a very substantial reduction in disk space usage
      during <literal>make check-world</literal>, since that sequence involves
      creation of numerous temporary installations.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [137e7c164] 2014-10-16 15:22:17 -0400
Branch: REL9_2_STABLE [7c67b9365] 2014-10-16 15:22:20 -0400
Branch: REL9_1_STABLE [2784b68b3] 2014-10-16 15:22:23 -0400
Branch: REL9_0_STABLE [870a980aa] 2014-10-16 15:22:26 -0400
-->

    <listitem>
     <para>
      Support time zone abbreviations that change UTC offset from time to
      time (Tom Lane)
     </para>

     <para>
      Previously, <productname>PostgreSQL</productname> assumed that the UTC offset
      associated with a time zone abbreviation (such as <literal>EST</literal>)
      never changes in the usage of any particular locale.  However this
      assumption fails in the real world, so introduce the ability for a
      zone abbreviation to represent a UTC offset that sometimes changes.
      Update the zone abbreviation definition files to make use of this
      feature in timezone locales that have changed the UTC offset of their
      abbreviations since 1970 (according to the IANA timezone database).
      In such timezones, <productname>PostgreSQL</productname> will now associate the
      correct UTC offset with the abbreviation depending on the given date.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [9701f238b] 2014-10-03 17:44:56 -0400
Branch: REL9_2_STABLE [d7d546bbc] 2014-10-03 17:44:59 -0400
Branch: REL9_1_STABLE [252af79d9] 2014-10-03 17:45:03 -0400
Branch: REL9_0_STABLE [cc7bad30c] 2014-10-03 17:45:07 -0400
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [0190f0a76] 2014-12-24 16:35:40 -0500
Branch: REL9_2_STABLE [5c8665892] 2014-12-24 16:35:44 -0500
Branch: REL9_1_STABLE [310597e31] 2014-12-24 16:35:48 -0500
Branch: REL9_0_STABLE [8b70023af] 2014-12-24 16:35:54 -0500
-->

    <listitem>
     <para>
      Update time zone abbreviations lists (Tom Lane)
     </para>

     <para>
      Add CST (China Standard Time) to our lists.
      Remove references to ADT as <quote>Arabia Daylight Time</quote>, an
      abbreviation that's been out of use since 2007; therefore, claiming
      there is a conflict with <quote>Atlantic Daylight Time</quote> doesn't seem
      especially helpful.
      Fix entirely incorrect GMT offsets for CKT (Cook Islands), FJT, and FJST
      (Fiji); we didn't even have them on the proper side of the date line.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [8470cd473] 2015-01-30 22:46:05 -0500
Branch: REL9_2_STABLE [c9048d353] 2015-01-30 22:46:12 -0500
Branch: REL9_1_STABLE [cb24cd3f4] 2015-01-30 22:46:17 -0500
Branch: REL9_0_STABLE [3553d9c6e] 2015-01-30 22:46:22 -0500
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [ab45d907b] 2014-11-17 12:08:25 -0500
Branch: REL9_2_STABLE [b1e996035] 2014-11-17 12:08:32 -0500
Branch: REL9_1_STABLE [b96c47a3d] 2014-11-17 12:08:39 -0500
Branch: REL9_0_STABLE [92979576e] 2014-11-17 12:08:46 -0500
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [c66199151] 2014-10-04 14:18:33 -0400
Branch: REL9_2_STABLE [8f75d7a25] 2014-10-04 14:18:36 -0400
Branch: REL9_1_STABLE [745723c9e] 2014-10-04 14:18:39 -0400
Branch: REL9_0_STABLE [b6391f587] 2014-10-04 14:18:43 -0400
-->

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2015a.
     </para>

     <para>
      The IANA timezone database has adopted abbreviations of the form
      <literal>A<replaceable>x</replaceable>ST</literal>/<literal>A<replaceable>x</replaceable>DT</literal>
      for all Australian time zones, reflecting what they believe to be
      current majority practice Down Under.  These names do not conflict
      with usage elsewhere (other than ACST for Acre Summer Time, which has
      been in disuse since 1994).  Accordingly, adopt these names into
      our <quote>Default</quote> timezone abbreviation set.
      The <quote>Australia</quote> abbreviation set now contains only CST, EAST,
      EST, SAST, SAT, and WST, all of which are thought to be mostly
      historical usage.  Note that SAST has also been changed to be South
      Africa Standard Time in the <quote>Default</quote> abbreviation set.
     </para>

     <para>
      Also, add zone abbreviations SRET (Asia/Srednekolymsk) and XJT
      (Asia/Urumqi), and use WSST/WSDT for western Samoa.  Also, there were
      DST law changes in Chile, Mexico, the Turks &amp; Caicos Islands
      (America/Grand_Turk), and Fiji.  There is a new zone
      Pacific/Bougainville for portions of Papua New Guinea.  Also, numerous
      corrections for historical (pre-1970) time zone data.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-5">
  <title>Release 9.3.5</title>

  <formalpara>
  <title>Release date:</title>
  <para>2014-07-24</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.4.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.5</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, this release corrects a logic error
    in <application>pg_upgrade</application>, as well as an index corruption problem in
    some GiST indexes.  See the first two changelog entries below to find out
    whether your installation has been affected and what steps you should take
    if so.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.4,
    see <xref linkend="release-9-3-4"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master [0f7482733] 2014-06-24 16:11:06 -0400
Branch: REL9_4_STABLE [dd5369047] 2014-06-24 16:11:06 -0400
Branch: REL9_3_STABLE [cc5841809] 2014-06-24 16:11:06 -0400
-->

    <listitem>
     <para>
      In <application>pg_upgrade</application>, remove <filename>pg_multixact</filename> files
      left behind by <application>initdb</application> (Bruce Momjian)
     </para>

     <para>
      If you used a pre-9.3.5 version of <application>pg_upgrade</application> to
      upgrade a database cluster to 9.3, it might have left behind a file
      <filename>$PGDATA/pg_multixact/offsets/0000</filename> that should not be
      there and will eventually cause problems in <command>VACUUM</command>.
      <emphasis>However, in common cases this file is actually valid and
      must not be removed.</emphasis>
      To determine whether your installation has this problem, run this
      query as superuser, in any database of the cluster:
<programlisting>
WITH list(file) AS (SELECT * FROM pg_ls_dir('pg_multixact/offsets'))
SELECT EXISTS (SELECT * FROM list WHERE file = '0000') AND
       NOT EXISTS (SELECT * FROM list WHERE file = '0001') AND
       NOT EXISTS (SELECT * FROM list WHERE file = 'FFFF') AND
       EXISTS (SELECT * FROM list WHERE file != '0000')
       AS file_0000_removal_required;
</programlisting>
      If this query returns <literal>t</literal>, manually remove the file
      <filename>$PGDATA/pg_multixact/offsets/0000</filename>.
      Do nothing if the query returns <literal>f</literal>.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master Release: REL9_4_BR [540ac7cea] 2014-05-13 15:15:13 +0300
Branch: REL9_3_STABLE [d5b912c90] 2014-05-13 15:27:14 +0300
Branch: REL9_2_STABLE [0d8d0d027] 2014-05-13 15:27:21 +0300
Branch: REL9_1_STABLE [1913d0f28] 2014-05-13 15:27:28 +0300
Branch: REL9_0_STABLE [c87c43f08] 2014-05-13 15:27:36 +0300
Branch: REL8_4_STABLE [e31d77c96] 2014-05-13 15:27:43 +0300
-->

    <listitem>
     <para>
      Correctly initialize padding bytes in <filename>contrib/btree_gist</filename>
      indexes on <type>bit</type> columns (Heikki Linnakangas)
     </para>

     <para>
      This error could result in incorrect query results due to values that
      should compare equal not being seen as equal.
      Users with GiST indexes on <type>bit</type> or <type>bit varying</type>
      columns should <command>REINDEX</command> those indexes after installing this
      update.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master Release: REL9_4_BR [4f7bb4b2a] 2014-05-08 14:50:22 +0300
Branch: REL9_3_STABLE [34572920c] 2014-05-08 14:43:04 +0300
Branch: REL9_2_STABLE [31633f992] 2014-05-08 14:43:39 +0300
Branch: REL9_1_STABLE [686a7194e] 2014-05-08 14:43:58 +0300
Branch: REL9_0_STABLE [8b4efe1f3] 2014-05-08 14:44:06 +0300
Branch: REL8_4_STABLE [be7830596] 2014-05-08 14:46:43 +0300
-->

    <listitem>
     <para>
      Protect against torn pages when deleting GIN list pages (Heikki
      Linnakangas)
     </para>

     <para>
      This fix prevents possible index corruption if a system crash occurs
      while the page update is being written to disk.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master Release: REL9_4_BR [7ca32e255] 2014-04-08 14:51:40 +0300
Branch: REL9_3_STABLE [601c01e08] 2014-04-08 14:51:49 +0300
Branch: REL9_2_STABLE [02b9fd73e] 2014-04-08 14:51:56 +0300
Branch: REL9_1_STABLE [ac0078c1d] 2014-04-08 14:52:01 +0300
Branch: REL9_0_STABLE [d034e9b3b] 2014-04-08 14:52:07 +0300
-->

    <listitem>
     <para>
      Don't clear the right-link of a GiST index page while replaying
      updates from WAL (Heikki Linnakangas)
     </para>

     <para>
      This error could lead to transiently wrong answers from GiST index
      scans performed in Hot Standby.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [c170655cc] 2014-06-09 16:31:11 -0400
Branch: REL9_3_STABLE [717c116f1] 2014-06-09 16:31:16 -0400
Branch: REL9_2_STABLE [93328b2df] 2014-06-09 16:30:46 -0400
-->

    <listitem>
     <para>
      Fix corner-case infinite loop during insertion into an SP-GiST text
      index (Tom Lane)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [1264ef31a] 2014-07-16 09:19:06 +0300
Branch: REL9_4_STABLE [9b3ef66af] 2014-07-16 09:20:20 +0300
Branch: REL9_3_STABLE [a4867d041] 2014-07-16 09:20:31 +0300
-->

    <listitem>
     <para>
      Fix incorrect answers from SP-GiST index searches
      with <literal>-|-</literal> (range adjacency) operator
      (Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master Release: REL9_4_BR [b0b263baa] 2014-06-09 15:17:23 -0400
Branch: REL9_3_STABLE [167a2535f] 2014-06-09 15:17:23 -0400
-->

    <listitem>
     <para>
      Fix wraparound handling for <filename>pg_multixact/members</filename>
      (&Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [f741300c9] 2014-06-27 14:43:53 -0400
Branch: REL9_4_STABLE [56f86bb76] 2014-06-27 14:43:52 -0400
Branch: REL9_3_STABLE [9a28c3752] 2014-06-27 14:43:52 -0400
-->

    <listitem>
     <para>
      Truncate <structname>pg_multixact</structname> during checkpoints, not
      during <command>VACUUM</command> (&Aacute;lvaro Herrera)
     </para>

     <para>
      This change ensures that <structname>pg_multixact</structname> segments can't be
      removed if they'd still be needed during WAL replay after a crash.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master Release: REL9_4_BR [2a8e1ac59] 2014-04-17 17:47:50 +0300
Branch: REL9_3_STABLE [95aa823eb] 2014-04-17 17:47:58 +0300
-->

    <listitem>
     <para>
      Fix possible inconsistency of all-visible flags after WAL recovery
      (Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [0f928a85e] 2014-05-05 14:43:39 -0400
Branch: REL9_3_STABLE [4f4ef042f] 2014-05-05 14:43:42 -0400
Branch: REL9_2_STABLE [c8fbeeb45] 2014-05-05 14:43:46 -0400
Branch: REL9_1_STABLE [2f4ee3a2f] 2014-05-05 14:43:49 -0400
Branch: REL9_0_STABLE [7d5b68621] 2014-05-05 14:43:52 -0400
Branch: REL8_4_STABLE [3ada1fab8] 2014-05-05 14:43:55 -0400
-->

    <listitem>
     <para>
      Fix possibly-incorrect cache invalidation during nested calls
      to <function>ReceiveSharedInvalidMessages</function> (Andres Freund)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master Release: REL9_4_BR [1a917ae86] 2014-04-24 15:41:55 -0300
Branch: REL9_3_STABLE [c0bd128c8] 2014-04-24 15:41:55 -0300
-->

    <listitem>
     <para>
      Fix race condition when updating a tuple concurrently locked by
      another process (Andres Freund, &Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: REL9_3_STABLE [a2db7b7d0] 2014-06-26 10:41:59 -0700
Branch: REL9_2_STABLE [0cf16686b] 2014-06-26 10:42:03 -0700
Branch: REL9_1_STABLE [555d0b200] 2014-06-26 10:42:08 -0700
-->

    <listitem>
     <para>
      Fix <quote>could not find pathkey item to sort</quote> planner failures
      with <literal>UNION ALL</literal> over subqueries reading from tables with
      inheritance children (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [9e2f2d7a0] 2014-07-08 14:03:56 -0400
Branch: REL9_4_STABLE [ac45aa1dd] 2014-07-08 14:03:45 -0400
Branch: REL9_3_STABLE [6d36aee5b] 2014-07-08 14:03:19 -0400
Branch: REL9_2_STABLE [189bd09cb] 2014-07-08 14:03:23 -0400
Branch: REL9_1_STABLE [fa21a760b] 2014-07-08 14:03:26 -0400
Branch: REL9_0_STABLE [2865d5952] 2014-07-08 14:03:30 -0400
Branch: REL8_4_STABLE [2e7469dc8] 2014-07-08 14:03:32 -0400
-->

    <listitem>
     <para>
      Don't assume a subquery's output is unique if there's a set-returning
      function in its targetlist (David Rowley)
     </para>

     <para>
      This oversight could lead to misoptimization of constructs
      like <literal>WHERE x IN (SELECT y, generate_series(1,10) FROM t GROUP
      BY y)</literal>.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [95811032d] 2014-04-29 13:12:46 -0400
Branch: REL9_3_STABLE [150a44e83] 2014-04-29 13:12:29 -0400
Branch: REL9_2_STABLE [0901dbab3] 2014-04-29 13:12:33 -0400
-->

    <listitem>
     <para>
      Improve planner to drop constant-NULL inputs
      of <literal>AND</literal>/<literal>OR</literal> when possible (Tom Lane)
     </para>

     <para>
      This change fixes some cases where the more aggressive parameter
      substitution done by 9.2 and later can lead to a worse plan than
      older versions produced.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [c7b353959] 2014-04-03 22:02:24 -0400
Branch: REL9_3_STABLE [d359f71ac] 2014-04-03 22:02:27 -0400
-->

    <listitem>
     <para>
      Ensure that the planner sees equivalent <literal>VARIADIC</literal> and
      non-<literal>VARIADIC</literal> function calls as equivalent (Tom Lane)
     </para>

     <para>
      This bug could for example result in failure to use expression indexes
      involving variadic functions.  It might be necessary to re-create such
      indexes, and/or re-create views including variadic function calls that
      should match the indexes, for the fix to be effective for existing 9.3
      installations.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [57d8c1270] 2014-06-24 21:22:40 -0700
Branch: REL9_4_STABLE [a331512de] 2014-06-24 21:22:43 -0700
Branch: REL9_3_STABLE [a1fc36495] 2014-06-24 21:22:47 -0700
-->

    <listitem>
     <para>
      Fix handling of nested <type>JSON</type> objects
      in <function>json_populate_recordset()</function> and friends
      (Michael Paquier, Tom Lane)
     </para>

     <para>
      A nested <type>JSON</type> object could result in previous fields of the
      parent object not being shown in the output.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [0ca6bda8e] 2014-05-09 12:55:31 -0400
Branch: REL9_3_STABLE [13c679995] 2014-05-09 12:55:03 -0400
Branch: REL9_2_STABLE [25c933c5c] 2014-05-09 12:55:06 -0400
-->

    <listitem>
     <para>
      Fix identification of input type category in <function>to_json()</function>
      and friends (Tom Lane)
     </para>

     <para>
      This is known to have led to inadequate quoting of <type>money</type>
      fields in the <type>JSON</type> result, and there may have been wrong
      results for other data types as well.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [3f8c8e3c6] 2014-05-01 15:19:06 -0400
Branch: REL9_3_STABLE [b72e90bc3] 2014-05-01 15:19:10 -0400
Branch: REL9_2_STABLE [8c43980a1] 2014-05-01 15:19:14 -0400
Branch: REL9_1_STABLE [db1fdc945] 2014-05-01 15:19:17 -0400
Branch: REL9_0_STABLE [7a4f114f3] 2014-05-01 15:19:20 -0400
Branch: REL8_4_STABLE [70debcf09] 2014-05-01 15:19:23 -0400
-->

    <listitem>
     <para>
      Fix failure to detoast fields in composite elements of structured
      types (Tom Lane)
     </para>

     <para>
      This corrects cases where TOAST pointers could be copied into other
      tables without being dereferenced.  If the original data is later
      deleted, it would lead to errors like <quote>missing chunk number 0
      for toast value ...</quote> when the now-dangling pointer is used.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [d68581483] 2014-07-11 19:12:35 -0400
Branch: REL9_4_STABLE [f280eff94] 2014-07-11 19:12:38 -0400
Branch: REL9_3_STABLE [b77e6b959] 2014-07-11 19:12:42 -0400
Branch: REL9_2_STABLE [261f954e7] 2014-07-11 19:12:45 -0400
Branch: REL9_1_STABLE [c45841f9e] 2014-07-11 19:12:48 -0400
Branch: REL9_0_STABLE [cd8ba91a0] 2014-07-11 19:12:51 -0400
Branch: REL8_4_STABLE [a81fbcfb3] 2014-07-11 19:12:56 -0400
-->

    <listitem>
     <para>
      Fix <quote>record type has not been registered</quote> failures with
      whole-row references to the output of Append plan nodes (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [04e5025be] 2014-05-07 14:25:11 -0400
Branch: REL9_3_STABLE [fc58c39d4] 2014-05-07 14:25:13 -0400
Branch: REL9_2_STABLE [022b5f2b2] 2014-05-07 14:25:17 -0400
Branch: REL9_1_STABLE [229101db4] 2014-05-07 14:25:22 -0400
Branch: REL9_0_STABLE [7f66ade71] 2014-05-07 14:25:25 -0400
Branch: REL8_4_STABLE [2a527baa3] 2014-05-07 14:25:28 -0400
-->

    <listitem>
     <para>
      Fix possible crash when invoking a user-defined function while
      rewinding a cursor (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [45b0f3572] 2014-06-19 22:14:26 -0400
Branch: REL9_4_STABLE [1044e79a0] 2014-06-19 22:13:44 -0400
Branch: REL9_3_STABLE [c1f8fb9bf] 2014-06-19 22:13:47 -0400
Branch: REL9_2_STABLE [b568d3836] 2014-06-19 22:13:51 -0400
Branch: REL9_1_STABLE [06d5eacbc] 2014-06-19 22:13:54 -0400
Branch: REL9_0_STABLE [83131e634] 2014-06-19 22:13:58 -0400
Branch: REL8_4_STABLE [d297c91d4] 2014-06-19 22:14:00 -0400
-->

    <listitem>
     <para>
      Fix query-lifespan memory leak while evaluating the arguments for a
      function in <literal>FROM</literal> (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [1567e659a] 2014-07-18 13:00:27 -0400
Branch: REL9_4_STABLE [4a66f0f2d] 2014-07-18 13:00:39 -0400
Branch: REL9_3_STABLE [5ef588b22] 2014-07-18 13:00:43 -0400
Branch: REL9_2_STABLE [a223b9e36] 2014-07-18 13:00:48 -0400
Branch: REL9_1_STABLE [8a817785a] 2014-07-18 13:00:52 -0400
Branch: REL9_0_STABLE [b8c24f7ab] 2014-07-18 13:00:57 -0400
Branch: REL8_4_STABLE [e0a233744] 2014-07-18 13:01:04 -0400
-->

    <listitem>
     <para>
      Fix session-lifespan memory leaks in regular-expression processing
      (Tom Lane, Arthur O'Dwyer, Greg Stark)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [fd90b5d57] 2014-06-10 22:48:16 -0400
Branch: REL9_4_STABLE [7f9fbb842] 2014-06-10 22:48:31 -0400
Branch: REL9_3_STABLE [87db9534a] 2014-06-10 22:48:39 -0400
Branch: REL9_2_STABLE [802323535] 2014-06-10 22:48:45 -0400
Branch: REL9_1_STABLE [62f134954] 2014-06-10 22:48:52 -0400
Branch: REL9_0_STABLE [4d5ea4290] 2014-06-10 22:48:59 -0400
Branch: REL8_4_STABLE [f3f40434b] 2014-06-10 22:49:08 -0400
-->

    <listitem>
     <para>
      Fix data encoding error in <filename>hungarian.stop</filename> (Tom Lane)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [a87a7dc8b] 2014-06-24 13:27:18 +0300
Branch: REL9_4_STABLE [1818ae0a7] 2014-06-24 13:31:06 +0300
Branch: REL9_3_STABLE [2a7512bc7] 2014-06-24 13:31:00 +0300
Branch: REL9_2_STABLE [1c9f9e888] 2014-06-24 13:30:54 +0300
Branch: REL9_1_STABLE [dd1a5b09b] 2014-06-24 13:30:41 +0300
-->

    <listitem>
     <para>
      Prevent foreign tables from being created with OIDS
      when <xref linkend="guc-default-with-oids"/> is true
      (Etsuro Fujita)
     </para>
    </listitem>

<!--
Author: Andres Freund <andres@anarazel.de>
Branch: master Release: REL9_4_BR [621a99a66] 2014-06-04 21:36:19 +0200
Branch: REL9_3_STABLE [edde59db1] 2014-06-04 23:26:08 +0200
Branch: REL9_2_STABLE [315442c01] 2014-06-04 23:25:52 +0200
Branch: REL9_1_STABLE [6bf6e528a] 2014-06-04 23:26:30 +0200
Branch: REL9_0_STABLE [037c6fb9f] 2014-06-04 23:27:10 +0200
Branch: REL8_4_STABLE [80d45ae4e] 2014-06-04 23:27:38 +0200
-->

    <listitem>
     <para>
      Fix liveness checks for rows that were inserted in the current
      transaction and then deleted by a now-rolled-back subtransaction
      (Andres Freund)
     </para>

     <para>
      This could cause problems (at least spurious warnings, and at worst an
      infinite loop) if <command>CREATE INDEX</command> or <command>CLUSTER</command> were
      done later in the same transaction.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [d19bd29f0] 2014-04-24 13:29:48 -0400
Branch: REL9_3_STABLE [12e41a5d7] 2014-04-24 13:29:56 -0400
Branch: REL9_2_STABLE [ea9ac7741] 2014-04-24 13:30:00 -0400
Branch: REL9_1_STABLE [70e7be264] 2014-04-24 13:30:04 -0400
Branch: REL9_0_STABLE [b7a3e1173] 2014-04-24 13:30:08 -0400
Branch: REL8_4_STABLE [82fbd88a7] 2014-04-24 13:30:14 -0400
-->

    <listitem>
     <para>
      Clear <structname>pg_stat_activity</structname>.<structfield>xact_start</structfield>
      during <command>PREPARE TRANSACTION</command> (Andres Freund)
     </para>

     <para>
      After the <command>PREPARE</command>, the originating session is no longer in
      a transaction, so it should not continue to display a transaction
      start time.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [6bdf4b9c7] 2014-07-15 13:24:07 -0400
Branch: REL9_4_STABLE [e45229bb6] 2014-07-15 13:24:07 -0400
Branch: REL9_3_STABLE [12c5bbdcb] 2014-07-15 13:24:07 -0400
Branch: REL9_2_STABLE [b42f09fc8] 2014-07-15 13:24:07 -0400
Branch: REL9_1_STABLE [a41dc7321] 2014-07-15 13:24:07 -0400
Branch: REL9_0_STABLE [bf08864b8] 2014-07-15 13:24:07 -0400
Branch: REL8_4_STABLE [4b767789d] 2014-07-15 13:24:07 -0400
-->

    <listitem>
     <para>
      Fix <command>REASSIGN OWNED</command> to not fail for text search objects
      (&Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [b7e51d9c0] 2014-06-27 14:43:46 -0400
Branch: REL9_4_STABLE [9eecc8a7c] 2014-06-27 14:43:46 -0400
Branch: REL9_3_STABLE [e86cfc4bb] 2014-06-27 14:43:45 -0400
-->

    <listitem>
     <para>
      Prevent <structname>pg_class</structname>.<structfield>relminmxid</structfield> values from
      going backwards during <command>VACUUM FULL</command> (&Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [41de93c53] 2014-04-30 13:26:26 -0400
Branch: REL9_3_STABLE [0652d77fb] 2014-04-30 13:26:29 -0400
-->

    <listitem>
     <para>
      Reduce indentation in rule/view dumps to improve readability and avoid
      excessive whitespace (Greg Stark, Tom Lane)
     </para>

     <para>
      This change reduces the amount of indentation applied to nested
      constructs, including some cases that the user probably doesn't think
      of as nested, such as UNION lists.  Previously, deeply nested
      constructs were printed with an amount of whitespace growing as
      O(N^2), which created a performance problem and even risk of
      out-of-memory failures.  Now the indentation is reduced modulo 40,
      which is initially odd to look at but seems to preserve readability
      better than simply limiting the indentation would do.
      Redundant parenthesization of UNION lists has been reduced as well.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [91e16b980] 2014-05-01 20:22:37 -0400
Branch: REL9_3_STABLE [e31193d49] 2014-05-01 20:22:39 -0400
-->

    <listitem>
     <para>
      Fix dumping of rules/views when subsequent addition of a column has
      resulted in multiple input columns matching a <literal>USING</literal>
      specification (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [9b35ddce9] 2014-07-19 14:28:52 -0400
Branch: REL9_4_STABLE [f0a497e4c] 2014-07-19 14:29:00 -0400
Branch: REL9_3_STABLE [b978ab5f6] 2014-07-19 14:29:05 -0400
-->

    <listitem>
     <para>
      Repair view printing for some cases involving functions
      in <literal>FROM</literal> that return a composite type containing dropped
      columns (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [5d8117e1f] 2014-04-05 18:16:08 -0400
Branch: REL9_3_STABLE [21aa47d01] 2014-04-05 18:16:11 -0400
Branch: REL9_2_STABLE [53463e247] 2014-04-05 18:16:14 -0400
Branch: REL9_1_STABLE [093d3da1d] 2014-04-05 18:16:17 -0400
Branch: REL9_0_STABLE [5c26ab659] 2014-04-05 18:16:20 -0400
Branch: REL8_4_STABLE [969735cf1] 2014-04-05 18:16:24 -0400
-->

    <listitem>
     <para>
      Block signals during postmaster startup (Tom Lane)
     </para>

     <para>
      This ensures that the postmaster will properly clean up after itself
      if, for example, it receives <systemitem>SIGINT</systemitem> while still
      starting up.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [fc752505a] 2014-04-02 17:11:24 -0400
Branch: REL9_3_STABLE [65183fb78] 2014-04-02 17:11:27 -0400
Branch: REL9_2_STABLE [029decfec] 2014-04-02 17:11:31 -0400
Branch: REL9_1_STABLE [b7a424371] 2014-04-02 17:11:34 -0400
-->

    <listitem>
     <para>
      Fix client host name lookup when processing <filename>pg_hba.conf</filename>
      entries that specify host names instead of IP addresses (Tom Lane)
     </para>

     <para>
      Ensure that reverse-DNS lookup failures are reported, instead of just
      silently not matching such entries.  Also ensure that we make only
      one reverse-DNS lookup attempt per connection, not one per host name
      entry, which is what previously happened if the lookup attempts failed.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [b203c57bb] 2014-04-04 22:03:35 -0400
Branch: REL9_3_STABLE [7d1a0f585] 2014-04-04 22:03:38 -0400
Branch: REL9_2_STABLE [6d25eb314] 2014-04-04 22:03:42 -0400
-->

    <listitem>
     <para>
      Allow the root user to use <literal>postgres -C variable</literal> and
      <literal>postgres --describe-config</literal> (MauMau)
     </para>

     <para>
      The prohibition on starting the server as root does not need to extend
      to these operations, and relaxing it prevents failure
      of <application>pg_ctl</application> in some scenarios.
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [be76a6d39] 2014-06-14 09:41:13 -0400
Branch: REL9_4_STABLE [6583a75b2] 2014-06-14 09:41:16 -0400
Branch: REL9_3_STABLE [1442b426e] 2014-06-14 09:41:17 -0400
Branch: REL9_2_STABLE [453a5d91d] 2014-06-14 09:41:17 -0400
Branch: REL9_1_STABLE [481831b43] 2014-06-14 09:41:18 -0400
Branch: REL9_0_STABLE [5f09c583c] 2014-06-14 09:41:18 -0400
Branch: REL8_4_STABLE [95cefd30e] 2014-06-14 09:41:18 -0400
-->

    <listitem>
     <para>
      Secure Unix-domain sockets of temporary postmasters started during
      <literal>make check</literal> (Noah Misch)
     </para>

     <para>
      Any local user able to access the socket file could connect as the
      server's bootstrap superuser, then proceed to execute arbitrary code as
      the operating-system user running the test, as we previously noted in
      CVE-2014-0067.  This change defends against that risk by placing the
      server's socket in a temporary, mode 0700 subdirectory
      of <filename>/tmp</filename>.  The hazard remains however on platforms where
      Unix sockets are not supported, notably Windows, because then the
      temporary postmaster must accept local TCP connections.
     </para>

     <para>
      A useful side effect of this change is to simplify
      <literal>make check</literal> testing in builds that
      override <literal>DEFAULT_PGSOCKET_DIR</literal>.  Popular non-default values
      like <filename>/var/run/postgresql</filename> are often not writable by the
      build user, requiring workarounds that will no longer be necessary.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [abe075dff] 2014-04-04 23:09:35 -0400
Branch: REL9_3_STABLE [84520f91c] 2014-04-04 23:09:38 -0400
Branch: REL9_2_STABLE [1a496a12b] 2014-04-04 23:09:41 -0400
Branch: REL9_1_STABLE [af7738fe6] 2014-04-04 23:09:45 -0400
Branch: REL9_0_STABLE [634056567] 2014-04-04 23:09:49 -0400
-->

    <listitem>
     <para>
      Fix tablespace creation WAL replay to work on Windows (MauMau)
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master Release: REL9_4_BR [418093465] 2014-04-16 10:45:48 -0400
Branch: REL9_3_STABLE [f716c3250] 2014-04-16 10:45:48 -0400
Branch: REL9_2_STABLE [966f015b6] 2014-04-16 10:45:48 -0400
Branch: REL9_1_STABLE [bed499ed1] 2014-04-16 10:45:48 -0400
Branch: REL9_0_STABLE [a86b2daff] 2014-04-16 10:45:48 -0400
-->

    <listitem>
     <para>
      Fix detection of socket creation failures on Windows (Bruce Momjian)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [6862ca697] 2014-04-05 12:41:25 -0400
Branch: REL9_3_STABLE [18db2150c] 2014-04-05 12:41:28 -0400
Branch: REL9_2_STABLE [bdc3e95c2] 2014-04-05 12:41:31 -0400
Branch: REL9_1_STABLE [cb11f4d8d] 2014-04-05 12:41:34 -0400
Branch: REL9_0_STABLE [9500d8f89] 2014-04-05 12:41:38 -0400
Branch: REL8_4_STABLE [30e434bdf] 2014-04-05 12:41:40 -0400
-->

    <listitem>
     <para>
      On Windows, allow new sessions to absorb values of PGC_BACKEND
      parameters (such as <xref linkend="guc-log-connections"/>) from the
      configuration file (Amit Kapila)
     </para>

     <para>
      Previously, if such a parameter were changed in the file post-startup,
      the change would have no effect.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master Release: REL9_4_BR [503de5462] 2014-04-30 10:35:52 +0300
Branch: REL9_3_STABLE [8a90a39b4] 2014-04-30 10:35:46 +0300
Branch: REL9_2_STABLE [e2558e016] 2014-04-30 10:36:31 +0300
Branch: REL9_1_STABLE [94095e341] 2014-04-30 10:36:41 +0300
Branch: REL9_0_STABLE [c06b7219a] 2014-04-30 10:38:32 +0300
Branch: REL8_4_STABLE [e3f273ff6] 2014-04-30 10:39:03 +0300
-->

    <listitem>
     <para>
      Properly quote executable path names on Windows (Nikhil Deshpande)
     </para>

     <para>
      This oversight could cause <application>initdb</application>
      and <application>pg_upgrade</application> to fail on Windows, if the installation
      path contained both spaces and <literal>@</literal> signs.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [20561acf9] 2014-05-30 18:19:06 -0400
Branch: REL9_3_STABLE [4f5f4da79] 2014-05-30 18:19:14 -0400
Branch: REL9_2_STABLE [83ed4598b] 2014-05-30 18:18:20 -0400
Branch: REL9_1_STABLE [a784a39c4] 2014-05-30 18:18:24 -0400
Branch: REL9_0_STABLE [4f725bbc4] 2014-05-30 18:18:28 -0400
Branch: REL8_4_STABLE [ae41bb4be] 2014-05-30 18:18:32 -0400
-->

    <listitem>
     <para>
      Fix linking of <application>libpython</application> on macOS (Tom Lane)
     </para>

     <para>
      The method we previously used can fail with the Python library
      supplied by Xcode 5.0 and later.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [2f557167b] 2014-05-07 21:39:13 -0400
Branch: REL9_3_STABLE [b4f9c93ce] 2014-05-07 21:38:38 -0400
Branch: REL9_2_STABLE [f7672c8ce] 2014-05-07 21:38:41 -0400
Branch: REL9_1_STABLE [86888054a] 2014-05-07 21:38:44 -0400
Branch: REL9_0_STABLE [77e662827] 2014-05-07 21:38:47 -0400
Branch: REL8_4_STABLE [664ac3de7] 2014-05-07 21:38:50 -0400
-->

    <listitem>
     <para>
      Avoid buffer bloat in <application>libpq</application> when the server
      consistently sends data faster than the client can absorb it
      (Shin-ichi Morita, Tom Lane)
     </para>

     <para>
      <application>libpq</application> could be coerced into enlarging its input buffer
      until it runs out of memory (which would be reported misleadingly
      as <quote>lost synchronization with server</quote>).  Under ordinary
      circumstances it's quite far-fetched that data could be continuously
      transmitted more quickly than the <function>recv()</function> loop can
      absorb it, but this has been observed when the client is artificially
      slowed by scheduler constraints.
     </para>
    </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
Branch: master Release: REL9_4_BR [585bca393] 2014-04-16 18:58:10 +0200
Branch: REL9_3_STABLE [cc269272c] 2014-04-16 18:58:55 +0200
Branch: REL9_2_STABLE [b764080ee] 2014-04-16 18:59:11 +0200
Branch: REL9_1_STABLE [c4bf15b9c] 2014-04-16 18:59:28 +0200
Branch: REL9_0_STABLE [96752b02d] 2014-04-16 18:59:37 +0200
Branch: REL8_4_STABLE [b4ae2e37d] 2014-04-16 18:59:48 +0200
-->

    <listitem>
     <para>
      Ensure that LDAP lookup attempts in <application>libpq</application> time out as
      intended (Laurenz Albe)
     </para>
    </listitem>

<!--
Author: Michael Meskes <meskes@postgresql.org>
Branch: master Release: REL9_4_BR [8d6a07fa0] 2014-05-06 13:09:51 +0200
Branch: REL9_3_STABLE [b4eeb9d58] 2014-05-06 13:04:30 +0200
Branch: REL9_2_STABLE [3a024c110] 2014-05-06 13:14:01 +0200
Branch: REL9_1_STABLE [fb66e88cf] 2014-05-06 13:20:22 +0200
Branch: REL9_0_STABLE [91c8c106f] 2014-05-06 13:24:13 +0200

Author: Michael Meskes <meskes@postgresql.org>
Branch: master Release: REL9_4_BR [f91796853] 2014-04-09 11:23:38 +0200
Branch: REL9_3_STABLE [3b8fda676] 2014-04-09 11:38:40 +0200
Branch: REL9_2_STABLE [2b3136de9] 2014-04-09 11:43:13 +0200
Branch: REL9_1_STABLE [0de106836] 2014-04-09 12:04:33 +0200
Branch: REL9_0_STABLE [0c2eb989e] 2014-04-09 12:12:32 +0200
-->

    <listitem>
     <para>
      Fix <application>ecpg</application> to do the right thing when an array
      of <type>char *</type> is the target for a FETCH statement returning more
      than one row, as well as some other array-handling fixes
      (Ashutosh Bapat)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [62215de29] 2014-03-29 17:34:00 -0400
Branch: REL9_3_STABLE [3080bbaa9] 2014-03-29 17:34:03 -0400
-->

    <listitem>
     <para>
      Fix <application>pg_dump</application> to cope with a materialized view that
      depends on a table's primary key (Tom Lane)
     </para>

     <para>
      This occurs if the view's query relies on functional dependency to
      abbreviate a <literal>GROUP BY</literal> list.  <application>pg_dump</application> got
      sufficiently confused that it dumped the materialized view as a
      regular view.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [19f2d6cda] 2014-03-18 10:38:25 -0400
Branch: REL9_3_STABLE [63817f86b] 2014-03-18 10:38:38 -0400
-->

    <listitem>
     <para>
      Fix parsing of <application>pg_dumpall</application>'s <option>-i</option> switch
      (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [c81e63d85] 2014-06-12 20:14:32 -0400
Branch: REL9_4_STABLE [c3c1401ca] 2014-06-12 20:14:36 -0400
Branch: REL9_3_STABLE [a11577f47] 2014-06-12 20:14:39 -0400
Branch: REL9_2_STABLE [ce7fc4fbb] 2014-06-12 20:14:46 -0400
Branch: REL9_1_STABLE [294a48985] 2014-06-12 20:14:49 -0400
Branch: REL9_0_STABLE [3fec825f9] 2014-06-12 20:14:52 -0400
Branch: REL8_4_STABLE [6adddac8a] 2014-06-12 20:14:55 -0400
-->

    <listitem>
     <para>
      Fix <application>pg_restore</application>'s processing of old-style large object
      comments (Tom Lane)
     </para>

     <para>
      A direct-to-database restore from an archive file generated by a
      pre-9.0 version of <application>pg_dump</application> would usually fail if the
      archive contained more than a few comments for large objects.
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master [3088cc370] 2014-07-07 13:24:08 -0400
Branch: REL9_4_STABLE [f64fe2cbe] 2014-07-07 13:24:08 -0400
Branch: REL9_3_STABLE [f1d7ff5bb] 2014-07-07 13:24:08 -0400
Branch: REL9_2_STABLE [759c9fb63] 2014-07-07 13:24:08 -0400
-->

    <listitem>
     <para>
      Fix <application>pg_upgrade</application> for cases where the new server creates
      a TOAST table but the old version did not (Bruce Momjian)
     </para>

     <para>
      This rare situation would manifest as <quote>relation OID mismatch</quote>
      errors.
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master [a61daa14d] 2014-07-02 15:29:38 -0400
Branch: REL9_4_STABLE [b446a384b] 2014-07-02 15:29:38 -0400
Branch: REL9_3_STABLE [3d2e18510] 2014-07-02 15:29:38 -0400

Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [78db307bb] 2014-07-21 11:41:53 -0400
Branch: REL9_4_STABLE [d122387d7] 2014-07-21 11:42:00 -0400
Branch: REL9_3_STABLE [e7984cca0] 2014-07-21 11:42:05 -0400
-->

    <listitem>
     <para>
      In <application>pg_upgrade</application>,
      preserve <structname>pg_database</structname>.<structfield>datminmxid</structfield>
      and <structname>pg_class</structname>.<structfield>relminmxid</structfield> values from the
      old cluster, or insert reasonable values when upgrading from pre-9.3;
      also defend against unreasonable values in the core server
      (Bruce Momjian, &Aacute;lvaro Herrera, Tom Lane)
     </para>

     <para>
      These changes prevent scenarios in which autovacuum might insist on
      scanning the entire cluster's contents immediately upon starting the
      new cluster, or in which tracking of unfrozen MXID values might be
      disabled completely.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [e416830a2] 2014-05-20 12:20:47 -0400
Branch: REL9_3_STABLE [0266a9c78] 2014-05-20 12:20:52 -0400
Branch: REL9_2_STABLE [31f579f09] 2014-05-20 12:20:57 -0400
-->

    <listitem>
     <para>
      Prevent <filename>contrib/auto_explain</filename> from changing the output of
      a user's <command>EXPLAIN</command> (Tom Lane)
     </para>

     <para>
      If <filename>auto_explain</filename> is active, it could cause
      an <literal>EXPLAIN (ANALYZE, TIMING OFF)</literal> command to nonetheless
      print timing information.
     </para>
    </listitem>

<!--
Author: Joe Conway <mail@joeconway.com>
Branch: master [1dde5782e] 2014-06-20 12:24:59 -0700
Branch: REL9_4_STABLE [9d884a34c] 2014-06-20 12:26:26 -0700
Branch: REL9_3_STABLE [b3a3f3d2f] 2014-06-20 12:26:43 -0700
Branch: REL9_2_STABLE [3e2cfa42f] 2014-06-20 12:27:04 -0700
-->

    <listitem>
     <para>
      Fix query-lifespan memory leak in <filename>contrib/dblink</filename>
      (MauMau, Joe Conway)
     </para>
    </listitem>

<!--
Author: Bruce Momjian <bruce@momjian.us>
Branch: master Release: REL9_4_BR [9fe55259f] 2014-04-17 12:37:53 -0400
Branch: REL9_3_STABLE [fc72e94a1] 2014-04-17 12:37:53 -0400
Branch: REL9_2_STABLE [ea8725a8b] 2014-04-17 12:37:53 -0400
Branch: REL9_1_STABLE [fc02b87e2] 2014-04-17 12:37:53 -0400
Branch: REL9_0_STABLE [a1b9c4630] 2014-04-17 12:37:53 -0400
Branch: REL8_4_STABLE [df2e62603] 2014-04-17 12:37:53 -0400
-->

    <listitem>
     <para>
      In <filename>contrib/pgcrypto</filename> functions, ensure sensitive
      information is cleared from stack variables before returning
      (Marko Kreen)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [9d0826c59] 2014-06-30 16:59:19 -0400
Branch: REL9_4_STABLE [37a4d3d70] 2014-06-30 16:59:44 -0400
Branch: REL9_3_STABLE [f14e40852] 2014-06-30 17:00:22 -0400
Branch: REL9_2_STABLE [f6d6b7b1e] 2014-06-30 17:00:40 -0400
-->

    <listitem>
     <para>
      Prevent use of already-freed memory in
      <filename>contrib/pgstattuple</filename>'s <function>pgstat_heap()</function>
      (Noah Misch)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master Release: REL9_4_BR [c941aed96] 2014-05-29 13:51:02 -0400
Branch: REL9_3_STABLE [961dd203a] 2014-05-29 13:51:05 -0400
Branch: REL9_2_STABLE [2fb9fb661] 2014-05-29 13:51:09 -0400
Branch: REL9_1_STABLE [3606754da] 2014-05-29 13:51:12 -0400
Branch: REL9_0_STABLE [b2f6754d2] 2014-05-29 13:51:15 -0400
Branch: REL8_4_STABLE [fd785441f] 2014-05-29 13:51:18 -0400
-->

    <listitem>
     <para>
      In <filename>contrib/uuid-ossp</filename>, cache the state of the OSSP UUID
      library across calls (Tom Lane)
     </para>

     <para>
      This improves the efficiency of UUID generation and reduces the amount
      of entropy drawn from <filename>/dev/urandom</filename>, on platforms that
      have that.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [b1864fabf] 2014-07-19 15:00:50 -0400
Branch: REL9_4_STABLE [e5ea60e80] 2014-07-19 15:01:05 -0400
Branch: REL9_3_STABLE [bd5458f52] 2014-07-19 15:01:12 -0400
Branch: REL9_2_STABLE [7d09e4854] 2014-07-19 15:01:18 -0400
Branch: REL9_1_STABLE [40ccb6530] 2014-07-19 15:01:28 -0400
Branch: REL9_0_STABLE [7659b6913] 2014-07-19 15:01:38 -0400
Branch: REL8_4_STABLE [c51da696b] 2014-07-19 15:01:45 -0400
-->

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2014e
      for DST law changes in Crimea, Egypt, and Morocco.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-4">
  <title>Release 9.3.4</title>

  <formalpara>
  <title>Release date:</title>
  <para>2014-03-20</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.3.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.4</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, the error fixed in the first changelog entry below could have
    resulted in corrupt data on standby servers.  It may be prudent to
    reinitialize standby servers from fresh base backups after installing
    this update.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.3,
    see <xref linkend="release-9-3-3"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [6bfa88acd] 2014-02-27 11:13:39 -0300
Branch: REL9_3_STABLE [9a57858f1] 2014-02-27 11:23:24 -0300
-->

    <listitem>
     <para>
      Fix WAL replay of locking an already-updated tuple (Andres Freund,
      &Aacute;lvaro Herrera)
     </para>

     <para>
      This error caused updated rows to not be found by index scans, resulting
      in inconsistent query results depending on whether an index scan was
      used.  Subsequent processing could result in constraint violations,
      since the previously updated row would not be found by later index
      searches, thus possibly allowing conflicting rows to be inserted.
      Since this error is in WAL replay, it would only manifest during crash
      recovery or on standby servers.  The improperly-replayed case most
      commonly arises when a table row that is referenced by a foreign-key
      constraint is updated concurrently with creation of a referencing row.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [fecfc2b91] 2014-03-12 10:04:57 +0200
Branch: REL9_3_STABLE [4738cc356] 2014-03-12 10:05:46 +0200
Branch: REL9_2_STABLE [91f932cf4] 2014-03-12 10:07:22 +0200
Branch: REL9_1_STABLE [63e59c259] 2014-03-12 10:09:22 +0200
Branch: REL9_0_STABLE [9954e1f03] 2014-03-12 10:09:43 +0200
Branch: REL8_4_STABLE [e2bccdfcc] 2014-03-12 10:10:04 +0200
-->

    <listitem>
     <para>
      Restore GIN metapages unconditionally to avoid torn-page risk
      (Heikki Linnakangas)
     </para>

     <para>
      Although this oversight could theoretically result in a corrupted
      index, it is unlikely to have caused any problems in practice, since
      the active part of a GIN metapage is smaller than a standard 512-byte
      disk sector.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [7bae0284e] 2014-03-13 12:02:54 -0400
Branch: REL9_3_STABLE [0d11fed8e] 2014-03-13 12:02:56 -0400
Branch: REL9_2_STABLE [bbe9621a9] 2014-03-13 12:03:00 -0400
Branch: REL9_1_STABLE [7bfdf10f5] 2014-03-13 12:03:03 -0400
Branch: REL9_0_STABLE [7aea1050e] 2014-03-13 12:03:07 -0400
-->

    <listitem>
     <para>
      Avoid race condition in checking transaction commit status during
      receipt of a <command>NOTIFY</command> message (Marko Tiikkaja)
     </para>

     <para>
      This prevents a scenario wherein a sufficiently fast client might
      respond to a notification before database updates made by the
      notifier have become visible to the recipient.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [bf4052faa] 2014-03-06 11:37:02 -0500
Branch: REL9_3_STABLE [3973034e6] 2014-03-06 11:37:04 -0500
-->

    <listitem>
     <para>
      Allow materialized views to be referenced in <command>UPDATE</command>
      and <command>DELETE</command> commands (Michael Paquier)
     </para>

     <para>
      Previously such queries failed with a complaint about not being able
      to lock rows in the materialized view.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [9662143f0] 2014-03-01 15:20:56 -0500
Branch: REL9_3_STABLE [f5f21315d] 2014-03-01 15:21:00 -0500
Branch: REL9_2_STABLE [03e6423fc] 2014-03-01 15:21:04 -0500
Branch: REL9_1_STABLE [a9eb4924a] 2014-03-01 15:21:07 -0500
Branch: REL9_0_STABLE [43af0e8c6] 2014-03-01 15:21:11 -0500
Branch: REL8_4_STABLE [b6e143458] 2014-03-01 15:21:13 -0500
-->

    <listitem>
     <para>
      Allow regular-expression operators to be terminated early by query
      cancel requests (Tom Lane)
     </para>

     <para>
      This prevents scenarios wherein a pathological regular expression
      could lock up a server process uninterruptibly for a long time.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [a222f7fda] 2014-02-18 12:44:20 -0500
Branch: REL9_3_STABLE [0aaa42241] 2014-02-18 12:44:24 -0500
Branch: REL9_2_STABLE [d7cd6a9d5] 2014-02-18 12:44:27 -0500
Branch: REL9_1_STABLE [e6f7fe983] 2014-02-18 12:44:30 -0500
Branch: REL9_0_STABLE [19d66ab05] 2014-02-18 12:44:33 -0500
Branch: REL8_4_STABLE [dd378dd1e] 2014-02-18 12:44:36 -0500
-->

    <listitem>
     <para>
      Remove incorrect code that tried to allow <literal>OVERLAPS</literal> with
      single-element row arguments (Joshua Yanovski)
     </para>

     <para>
      This code never worked correctly, and since the case is neither
      specified by the SQL standard nor documented, it seemed better to
      remove it than fix it.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [7c3187494] 2014-03-06 19:31:05 -0500
Branch: REL9_3_STABLE [f557826f8] 2014-03-06 19:31:09 -0500
Branch: REL9_2_STABLE [5ec41e345] 2014-03-06 19:31:12 -0500
Branch: REL9_1_STABLE [f3e3f6c5b] 2014-03-06 19:31:16 -0500
Branch: REL9_0_STABLE [bed1259e5] 2014-03-06 19:31:19 -0500
Branch: REL8_4_STABLE [f043bddfe] 2014-03-06 19:31:22 -0500
-->

    <listitem>
     <para>
      Avoid getting more than <literal>AccessShareLock</literal> when de-parsing a
      rule or view (Dean Rasheed)
     </para>

     <para>
      This oversight resulted in <application>pg_dump</application> unexpectedly
      acquiring <literal>RowExclusiveLock</literal> locks on tables mentioned as
      the targets of <literal>INSERT</literal>/<literal>UPDATE</literal>/<literal>DELETE</literal>
      commands in rules.  While usually harmless, that could interfere with
      concurrent transactions that tried to acquire, for example,
      <literal>ShareLock</literal> on those tables.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [fccebe421] 2014-02-25 16:04:06 -0500
Branch: REL9_3_STABLE [4162a55c7] 2014-02-25 16:04:09 -0500
Branch: REL9_2_STABLE [00283cae1] 2014-02-25 16:04:12 -0500
Branch: REL9_1_STABLE [3e2db4c80] 2014-02-25 16:04:16 -0500
Branch: REL9_0_STABLE [1e0fb6a2c] 2014-02-25 16:04:20 -0500
-->

    <listitem>
     <para>
      Improve performance of index endpoint probes during planning (Tom Lane)
     </para>

     <para>
      This change fixes a significant performance problem that occurred
      when there were many not-yet-committed rows at the end of the index,
      which is a common situation for indexes on sequentially-assigned
      values such as timestamps or sequence-generated identifiers.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [77585bce0] 2014-02-21 17:10:46 -0500
Branch: REL9_3_STABLE [e8655a77f] 2014-02-21 17:10:49 -0500
-->

    <listitem>
     <para>
      Use non-default selectivity estimates for
      <literal><replaceable>value</replaceable> IN (<replaceable>list</replaceable>)</literal> and
      <literal><replaceable>value</replaceable> <replaceable>operator</replaceable> ANY
      (<replaceable>array</replaceable>)</literal>
      expressions when the righthand side is a stable expression (Tom Lane)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [2b4f2ab33] 2014-03-05 13:03:29 -0300
Branch: REL9_3_STABLE [13ea43ab8] 2014-03-05 13:03:29 -0300
-->

    <listitem>
     <para>
      Remove the correct per-database statistics file during <command>DROP
      DATABASE</command> (Tomas Vondra)
     </para>

     <para>
      This fix prevents a permanent leak of statistics file space.
      Users who have done many <command>DROP DATABASE</command> commands since
      upgrading to <productname>PostgreSQL</productname> 9.3 may wish to check their
      statistics directory and delete statistics files that do not
      correspond to any existing database.  Please note
      that <filename>db_0.stat</filename> should not be removed.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [94ae6ba74] 2014-03-06 21:38:51 +0200
Branch: REL9_3_STABLE [dcd1131c8] 2014-03-06 21:40:50 +0200
-->

    <listitem>
     <para>
      Fix <application>walsender</application> ping logic to avoid inappropriate
      disconnects under continuous load (Andres Freund, Heikki Linnakangas)
     </para>

     <para>
      <application>walsender</application> failed to send ping messages to the client
      if it was constantly busy sending WAL data; but it expected to see
      ping responses despite that, and would therefore disconnect
      once <xref linkend="guc-wal-sender-timeout"/> elapsed.
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: master [5c6d9fc4b] 2014-03-17 20:37:50 +0900
Branch: REL9_3_STABLE [385723405] 2014-03-17 20:41:12 +0900
Branch: REL9_2_STABLE [7899aa356] 2014-03-17 20:41:52 +0900
Branch: REL9_1_STABLE [65e8dbb18] 2014-03-17 20:42:35 +0900
-->

    <listitem>
     <para>
      Fix <application>walsender</application>'s failure to shut down cleanly when client
      is <application>pg_receivexlog</application> (Fujii Masao)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [956685f82] 2014-03-05 14:48:14 +0200
Branch: REL9_3_STABLE [a5363a696] 2014-03-05 14:46:56 +0200
Branch: REL9_2_STABLE [e7ec05562] 2014-03-05 14:45:55 +0200
-->

    <listitem>
     <para>
      Check WAL level and hot standby parameters correctly when doing crash
      recovery that will be followed by archive recovery (Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [af246c37c] 2014-03-05 13:51:19 +0200
Branch: REL9_3_STABLE [2cd72ba42] 2014-03-05 13:52:21 +0200
Branch: REL9_2_STABLE [931dc26b0] 2014-03-05 13:57:32 +0200
Branch: REL9_1_STABLE [7552d3d1a] 2014-03-05 13:58:14 +0200
Branch: REL9_0_STABLE [4521cc850] 2014-03-05 13:58:22 +0200
-->

    <listitem>
     <para>
      Fix test to see if hot standby connections can be allowed immediately
      after a crash (Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: REL9_3_STABLE [5a7e75849] 2014-02-20 10:46:54 +0200
-->

    <listitem>
     <para>
      Add read-only <xref linkend="guc-data-checksums"/> parameter to
      display whether page checksums are enabled (Heikki Linnakangas)
     </para>

     <para>
      Without this parameter, determining the state of checksum
      processing was difficult.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [6c461cb92] 2014-03-13 20:59:42 -0400
Branch: REL9_3_STABLE [41bd2cf55] 2014-03-13 20:59:45 -0400
Branch: REL9_2_STABLE [7a289bb6d] 2014-03-13 20:59:48 -0400
Branch: REL9_1_STABLE [f16ca9755] 2014-03-13 20:59:51 -0400
Branch: REL9_0_STABLE [dad55e1e9] 2014-03-13 20:59:55 -0400
Branch: REL8_4_STABLE [172c53e92] 2014-03-13 20:59:57 -0400
-->

    <listitem>
     <para>
      Prevent interrupts while reporting non-<literal>ERROR</literal> messages
      (Tom Lane)
     </para>

     <para>
      This guards against rare server-process freezeups due to recursive
      entry to <function>syslog()</function>, and perhaps other related problems.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [bd1154ede] 2014-03-16 23:22:21 -0300
Branch: REL9_3_STABLE [60829079d] 2014-03-16 23:22:22 -0300
Branch: REL9_2_STABLE [ba5946e86] 2014-03-16 23:22:22 -0300
Branch: REL9_1_STABLE [f84997c7e] 2014-03-16 23:22:22 -0300
-->

    <listitem>
     <para>
      Fix memory leak in PL/Perl when returning a composite result, including
      multiple-OUT-parameter cases (Alex Hunsaker)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [e85a5ffba] 2014-03-10 15:47:40 -0400
Branch: REL9_3_STABLE [f64f4c370] 2014-03-10 15:47:09 -0400
Branch: REL9_2_STABLE [b315b767f] 2014-03-10 15:47:13 -0400
-->

    <listitem>
     <para>
      Fix tracking of <application>psql</application> script line numbers
      during <literal>\copy</literal> from out-of-line data
      (Kumar Rajeev Rastogi, Amit Khandekar)
     </para>

     <para>
      <literal>\copy ... from</literal> incremented the script file line number
      for each data line, even if the data was not coming from the script
      file.  This mistake resulted in wrong line numbers being reported for
      any errors occurring later in the same script file.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [83204e100] 2014-03-07 16:36:40 -0500
Branch: REL9_3_STABLE [73f0483fd] 2014-03-07 16:36:50 -0500
-->

    <listitem>
     <para>
      Fix <application>contrib/postgres_fdw</application> to handle multiple join
      conditions properly (Tom Lane)
     </para>

     <para>
      This oversight could result in sending <literal>WHERE</literal> clauses to
      the remote server for execution even though the clauses are not known
      to have the same semantics on the remote server (for example, clauses
      that use non-built-in operators).  The query might succeed anyway,
      but it could also fail with errors from the remote server, or worse
      give silently wrong answers.
     </para>
    </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
Branch: master [7f3e17b48] 2014-02-18 14:45:58 +0100
Branch: REL9_3_STABLE [b88ecb002] 2014-02-18 14:49:41 +0100
Branch: REL9_2_STABLE [062deb313] 2014-02-18 14:50:19 +0100
Branch: REL9_1_STABLE [fae12f331] 2014-03-16 11:46:20 +0100
Branch: REL9_0_STABLE [665515539] 2014-03-16 11:47:37 +0100
-->

    <listitem>
     <para>
      Prevent intermittent <quote>could not reserve shared memory region</quote>
      failures on recent Windows versions (MauMau)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [aba7f5677] 2014-03-15 13:36:07 -0400
Branch: REL9_3_STABLE [b5de16997] 2014-03-15 13:36:24 -0400
Branch: REL9_2_STABLE [f2063b379] 2014-03-15 13:36:32 -0400
Branch: REL9_1_STABLE [2df1bf21c] 2014-03-15 13:36:41 -0400
Branch: REL9_0_STABLE [0033f5324] 2014-03-15 13:36:49 -0400
Branch: REL8_4_STABLE [6e6c2c2e1] 2014-03-15 13:36:57 -0400
-->

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2014a
      for DST law changes in Fiji and Turkey, plus historical changes in
      Israel and Ukraine.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-3">
  <title>Release 9.3.3</title>

  <formalpara>
  <title>Release date:</title>
  <para>2014-02-20</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.2.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.3</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, several of the issues corrected in this release could have
    resulted in corruption of foreign-key constraints; that is, there
    might now be referencing rows for which there is no matching row in
    the referenced table.  It may be worthwhile to recheck such
    constraints after installing this update.  The simplest way to do that
    is to drop and recreate each suspect constraint; however, that will
    require taking an exclusive lock on both tables, so it is unlikely to
    be acceptable in production databases.  Alternatively, you can do a
    manual join query between the two tables to look for unmatched rows.
   </para>

   <para>
    Note also the requirement for replication standby servers to be
    upgraded before their master server is upgraded.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.2,
    see <xref linkend="release-9-3-2"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [fea164a72] 2014-02-17 09:33:31 -0500
Branch: REL9_3_STABLE [475a1fbc4] 2014-02-17 09:33:32 -0500
Branch: REL9_2_STABLE [15a8f97b9] 2014-02-17 09:33:33 -0500
Branch: REL9_1_STABLE [5d320a16c] 2014-02-17 09:33:33 -0500
Branch: REL9_0_STABLE [789063697] 2014-02-17 09:33:37 -0500
Branch: REL8_4_STABLE [ff35425c8] 2014-02-17 09:33:38 -0500
-->

    <listitem>
     <para>
      Shore up <literal>GRANT ... WITH ADMIN OPTION</literal> restrictions
      (Noah Misch)
     </para>

     <para>
      Granting a role without <literal>ADMIN OPTION</literal> is supposed to
      prevent the grantee from adding or removing members from the granted
      role, but this restriction was easily bypassed by doing <literal>SET
      ROLE</literal> first.  The security impact is mostly that a role member can
      revoke the access of others, contrary to the wishes of his grantor.
      Unapproved role member additions are a lesser concern, since an
      uncooperative role member could provide most of his rights to others
      anyway by creating views or <literal>SECURITY DEFINER</literal> functions.
      (CVE-2014-0060)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [537cbd35c] 2014-02-17 09:33:31 -0500
Branch: REL9_3_STABLE [fc4a04a3c] 2014-02-17 09:33:32 -0500
Branch: REL9_2_STABLE [1d701d28a] 2014-02-17 09:33:33 -0500
Branch: REL9_1_STABLE [23b5a85e6] 2014-02-17 09:33:36 -0500
Branch: REL9_0_STABLE [c0ac4c75f] 2014-02-17 09:33:37 -0500
Branch: REL8_4_STABLE [823b9dc25] 2014-02-17 09:33:38 -0500
-->

    <listitem>
     <para>
      Prevent privilege escalation via manual calls to PL validator
      functions (Andres Freund)
     </para>

     <para>
      The primary role of PL validator functions is to be called implicitly
      during <command>CREATE FUNCTION</command>, but they are also normal SQL
      functions that a user can call explicitly.  Calling a validator on
      a function actually written in some other language was not checked
      for and could be exploited for privilege-escalation purposes.
      The fix involves adding a call to a privilege-checking function in
      each validator function.  Non-core procedural languages will also
      need to make this change to their own validator functions, if any.
      (CVE-2014-0061)
     </para>
    </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
Branch: master [5f173040e] 2014-02-17 09:33:31 -0500
Branch: REL9_3_STABLE [e1e0a4d79] 2014-02-17 09:33:32 -0500
Branch: REL9_2_STABLE [820ab11fb] 2014-02-17 09:33:33 -0500
Branch: REL9_1_STABLE [b5c574399] 2014-02-17 09:33:36 -0500
Branch: REL9_0_STABLE [43d4e965e] 2014-02-17 09:33:37 -0500
Branch: REL8_4_STABLE [e46476133] 2014-02-17 09:33:38 -0500
-->

    <listitem>
     <para>
      Avoid multiple name lookups during table and index DDL
      (Robert Haas, Andres Freund)
     </para>

     <para>
      If the name lookups come to different conclusions due to concurrent
      activity, we might perform some parts of the DDL on a different table
      than other parts.  At least in the case of <command>CREATE INDEX</command>,
      this can be used to cause the permissions checks to be performed
      against a different table than the index creation, allowing for a
      privilege escalation attack.
      (CVE-2014-0062)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [4318daecc] 2014-02-17 09:33:31 -0500
Branch: REL9_3_STABLE [e4a4fa223] 2014-02-17 09:33:32 -0500
Branch: REL9_2_STABLE [f416622be] 2014-02-17 09:33:33 -0500
Branch: REL9_1_STABLE [6a10e57b0] 2014-02-17 09:33:37 -0500
Branch: REL9_0_STABLE [b9c3bb1b3] 2014-02-17 09:33:38 -0500
Branch: REL8_4_STABLE [d0ed1a6c0] 2014-02-17 09:33:39 -0500
-->

    <listitem>
     <para>
      Prevent buffer overrun with long datetime strings (Noah Misch)
     </para>

     <para>
      The <literal>MAXDATELEN</literal> constant was too small for the longest
      possible value of type <type>interval</type>, allowing a buffer overrun
      in <function>interval_out()</function>.  Although the datetime input
      functions were more careful about avoiding buffer overrun, the limit
      was short enough to cause them to reject some valid inputs, such as
      input containing a very long timezone name.  The <application>ecpg</application>
      library contained these vulnerabilities along with some of its own.
      (CVE-2014-0063)
     </para>
    </listitem>

<!--
Author: Noah Misch <noah@leadboat.com>
Branch: master [31400a673] 2014-02-17 09:33:31 -0500
Branch: REL9_3_STABLE [7a362a176] 2014-02-17 09:33:32 -0500
Branch: REL9_2_STABLE [12bbce15d] 2014-02-17 09:33:33 -0500
Branch: REL9_1_STABLE [0b7026d96] 2014-02-17 09:33:37 -0500
Branch: REL9_0_STABLE [2c3203e18] 2014-02-17 09:33:38 -0500
Branch: REL8_4_STABLE [98be8a6ea] 2014-02-17 09:33:39 -0500
-->

    <listitem>
     <para>
      Prevent buffer overrun due to integer overflow in size calculations
      (Noah Misch, Heikki Linnakangas)
     </para>

     <para>
      Several functions, mostly type input functions, calculated an
      allocation size without checking for overflow.  If overflow did
      occur, a too-small buffer would be allocated and then written past.
      (CVE-2014-0064)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [01824385a] 2014-02-17 11:20:21 -0500
Branch: REL9_3_STABLE [e3208fec3] 2014-02-17 11:20:24 -0500
Branch: REL9_2_STABLE [655b665f7] 2014-02-17 11:20:27 -0500
Branch: REL9_1_STABLE [4741e3160] 2014-02-17 11:20:31 -0500
Branch: REL9_0_STABLE [45bf2404a] 2014-02-17 11:20:35 -0500
Branch: REL8_4_STABLE [69d2bc14a] 2014-02-17 11:20:38 -0500
-->

    <listitem>
     <para>
      Prevent overruns of fixed-size buffers
      (Peter Eisentraut, Jozef Mlich)
     </para>

     <para>
      Use <function>strlcpy()</function> and related functions to provide a clear
      guarantee that fixed-size buffers are not overrun.  Unlike the
      preceding items, it is unclear whether these cases really represent
      live issues, since in most cases there appear to be previous
      constraints on the size of the input string.  Nonetheless it seems
      prudent to silence all Coverity warnings of this type.
      (CVE-2014-0065)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [01824385a] 2014-02-17 11:20:21 -0500
Branch: REL9_3_STABLE [e3208fec3] 2014-02-17 11:20:24 -0500
Branch: REL9_2_STABLE [655b665f7] 2014-02-17 11:20:27 -0500
Branch: REL9_1_STABLE [4741e3160] 2014-02-17 11:20:31 -0500
Branch: REL9_0_STABLE [45bf2404a] 2014-02-17 11:20:35 -0500
Branch: REL8_4_STABLE [69d2bc14a] 2014-02-17 11:20:38 -0500
-->

    <listitem>
     <para>
      Avoid crashing if <function>crypt()</function> returns NULL (Honza Horak,
      Bruce Momjian)
     </para>

     <para>
      There are relatively few scenarios in which <function>crypt()</function>
      could return NULL, but <filename>contrib/chkpass</filename> would crash
      if it did.  One practical case in which this could be an issue is
      if <application>libc</application> is configured to refuse to execute unapproved
      hashing algorithms (e.g., <quote>FIPS mode</quote>).
      (CVE-2014-0066)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [6ef325429] 2014-02-17 11:24:32 -0500
Branch: REL9_3_STABLE [1ec5988f3] 2014-02-17 11:24:38 -0500
Branch: REL9_2_STABLE [ff3d533e5] 2014-02-17 11:24:42 -0500
Branch: REL9_1_STABLE [800a3744b] 2014-02-17 11:24:45 -0500
Branch: REL9_0_STABLE [369c229d2] 2014-02-17 11:24:48 -0500
Branch: REL8_4_STABLE [f58663ab1] 2014-02-17 11:24:51 -0500
-->

    <listitem>
     <para>
      Document risks of <literal>make check</literal> in the regression testing
      instructions (Noah Misch, Tom Lane)
     </para>

     <para>
      Since the temporary server started by <literal>make check</literal>
      uses <quote>trust</quote> authentication, another user on the same machine
      could connect to it as database superuser, and then potentially
      exploit the privileges of the operating-system user who started the
      tests.  A future release will probably incorporate changes in the
      testing procedure to prevent this risk, but some public discussion is
      needed first.  So for the moment, just warn people against using
      <literal>make check</literal> when there are untrusted users on the
      same machine.
      (CVE-2014-0067)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [3b97e6823] 2013-12-16 11:29:50 -0300
Branch: REL9_3_STABLE [8e9a16ab8] 2013-12-16 11:29:51 -0300
-->

    <listitem>
     <para>
      Rework tuple freezing protocol
      (&Aacute;lvaro Herrera, Andres Freund)
     </para>

     <para>
      The logic for tuple freezing was unable to handle some cases involving
      freezing of
      <link linkend="vacuum-for-multixact-wraparound"><firstterm>multixact</firstterm>
      IDs</link>, with the practical effect that shared row-level locks
      might be forgotten once old enough.
     </para>

     <para>
      Fixing this required changing the WAL record format for tuple
      freezing.  While this is no issue for standalone servers, when using
      replication it means that <emphasis>standby servers must be upgraded
      to 9.3.3 or later before their masters are</emphasis>.  An older standby will
      be unable to interpret freeze records generated by a newer master, and
      will fail with a PANIC message.  (In such a case, upgrading the
      standby should be sufficient to let it resume execution.)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [801c2dc72] 2014-02-13 19:36:31 -0300
Branch: REL9_3_STABLE [fb47de2be] 2014-02-13 19:30:30 -0300
-->

    <listitem>
     <para>
      Create separate GUC parameters to control multixact freezing
      (&Aacute;lvaro Herrera)
     </para>

     <para>
      9.3 requires multixact tuple labels to be frozen before
      they grow too old, in the same fashion as plain transaction ID labels
      have been frozen for some time.  Previously, the transaction ID
      freezing parameters were used for multixact IDs too; but since
      the consumption rates of transaction IDs and multixact IDs can be
      quite different, this did not work very well.  Introduce new settings
      <xref linkend="guc-vacuum-multixact-freeze-min-age"/>,
      <xref linkend="guc-vacuum-multixact-freeze-table-age"/>, and
      <xref linkend="guc-autovacuum-multixact-freeze-max-age"/>
      to control when to freeze multixacts.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [11ac4c73c] 2013-12-18 13:45:51 -0300
Branch: REL9_3_STABLE [db1014bc4] 2013-12-18 13:31:27 -0300
-->

    <listitem>
     <para>
      Account for remote row locks propagated by local updates
      (&Aacute;lvaro Herrera)
     </para>

     <para>
      If a row was locked by transaction A, and transaction B updated it,
      the new version of the row created by B would be locked by A, yet
      visible only to B.  If transaction B then again updated the row, A's
      lock wouldn't get checked, thus possibly allowing B to complete when
      it shouldn't.  This case is new in 9.3 since prior versions did not
      have any types of row locking that would permit another transaction
      to update the row at all.
     </para>

     <para>
      This oversight could allow referential integrity checks to give false
      positives (for instance, allow deletes that should have been rejected).
      Applications using the new commands <literal>SELECT FOR KEY SHARE</literal>
      and <literal>SELECT FOR NO KEY UPDATE</literal> might also have suffered
      locking failures of this kind.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [07aeb1fec] 2013-12-05 12:21:55 -0300
Branch: REL9_3_STABLE [c6cd27e36] 2013-12-05 12:21:55 -0300
-->

    <listitem>
     <para>
      Prevent <quote>forgetting</quote> valid row locks when one of several
      holders of a row lock aborts (&Aacute;lvaro Herrera)
     </para>

     <para>
      This was yet another mechanism by which a shared row lock could be
      lost, thus possibly allowing updates that should have been prevented
      by foreign-key constraints.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [312bde3d4] 2013-12-05 17:47:51 -0300
Branch: REL9_3_STABLE [2dcc48c35] 2013-12-05 17:47:51 -0300
-->

    <listitem>
     <para>
      Fix incorrect logic during update chain locking
      (&Aacute;lvaro Herrera)
     </para>

     <para>
      This mistake could result in spurious <quote>could not serialize access
      due to concurrent update</quote> errors in <literal>REPEATABLE READ</literal>
      and <literal>SERIALIZABLE</literal> transaction isolation modes.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [a50d97625] 2014-01-02 18:17:07 -0300
Branch: REL9_3_STABLE [03db79459] 2014-01-02 18:17:07 -0300
-->

    <listitem>
     <para>
      Handle wraparound correctly during extension or truncation
      of <filename>pg_multixact/members</filename>
      (Andres Freund, &Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [638cf09e7] 2014-01-02 18:17:29 -0300
Branch: REL9_3_STABLE [948a3dfbb] 2014-01-02 18:17:29 -0300
-->

    <listitem>
     <para>
      Fix handling of 5-digit filenames in <filename>pg_multixact/members</filename>
      (&Aacute;lvaro Herrera)
     </para>

     <para>
      As of 9.3, these names can be more than 4 digits, but the directory
      cleanup code ignored such files.
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [d881dd623] 2013-12-13 17:16:25 -0300
Branch: REL9_3_STABLE [0bc00363b] 2013-12-13 17:16:25 -0300
-->

    <listitem>
     <para>
      Improve performance of multixact cache code
      (&Aacute;lvaro Herrera)
     </para>
    </listitem>

<!--
Author: Alvaro Herrera <alvherre@alvh.no-ip.org>
Branch: master [13aa62443] 2013-12-19 16:53:49 -0300
Branch: REL9_3_STABLE [85d3b3c3a] 2013-12-19 16:39:59 -0300
-->

    <listitem>
     <para>
      Optimize updating a row that's already locked by the same transaction
      (Andres Freund, &Aacute;lvaro Herrera)
     </para>

     <para>
      This fixes a performance regression from pre-9.3 versions when doing
      <literal>SELECT FOR UPDATE</literal> followed by <literal>UPDATE/DELETE</literal>.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [4d894b41c] 2014-02-14 15:15:09 +0200
Branch: REL9_3_STABLE [762bd379a] 2014-02-14 15:18:34 +0200
-->

    <listitem>
     <para>
      During archive recovery, prefer highest timeline number when WAL
      segments with the same ID are present in both the archive
      and <filename>pg_xlog/</filename> (Kyotaro Horiguchi)
     </para>

     <para>
      Previously, not-yet-archived segments could get ignored during
      recovery.  This reverts an undesirable behavioral change in 9.3.0
      back to the way things worked pre-9.3.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [6f2aead1f] 2014-02-12 14:52:16 -0500
Branch: REL9_3_STABLE [7190f7a34] 2014-02-12 14:52:20 -0500
Branch: REL9_2_STABLE [bc7ab301a] 2014-02-12 14:52:23 -0500
Branch: REL9_1_STABLE [a69cc9b2c] 2014-02-12 14:52:26 -0500
Branch: REL9_0_STABLE [7fedd79b7] 2014-02-12 14:52:29 -0500
Branch: REL8_4_STABLE [9620fede9] 2014-02-12 14:52:32 -0500
-->

    <listitem>
     <para>
      Fix possible mis-replay of WAL records when some segments of a
      relation aren't full size (Greg Stark, Tom Lane)
     </para>

     <para>
      The WAL update could be applied to the wrong page, potentially many
      pages past where it should have been.  Aside from corrupting data,
      this error has been observed to result in significant <quote>bloat</quote>
      of standby servers compared to their masters, due to updates being
      applied far beyond where the end-of-file should have been.  This
      failure mode does not appear to be a significant risk during crash
      recovery, only when initially synchronizing a standby created from a
      base backup taken from a quickly-changing master.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [d59ff6c11] 2014-01-08 15:03:09 +0200
Branch: REL9_3_STABLE [425bef6ee] 2014-01-08 14:32:22 +0200
Branch: REL9_2_STABLE [82c75f9dd] 2014-01-08 14:28:55 +0200
Branch: REL9_1_STABLE [e56430c62] 2014-01-08 14:33:58 +0200
Branch: REL9_0_STABLE [5301c8395] 2014-01-08 14:34:21 +0200
-->

    <listitem>
     <para>
      Fix bug in determining when recovery has reached consistency
      (Tomonari Katsumata, Heikki Linnakangas)
     </para>

     <para>
      In some cases WAL replay would mistakenly conclude that the database
      was already consistent at the start of replay, thus possibly allowing
      hot-standby queries before the database was really consistent.  Other
      symptoms such as <quote>PANIC: WAL contains references to invalid
      pages</quote> were also possible.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [a49633d8d] 2013-12-13 14:15:04 +0200
Branch: REL9_3_STABLE [615299cf6] 2013-12-13 14:23:02 +0200
-->

    <listitem>
     <para>
      Fix WAL logging of visibility map changes (Heikki Linnakangas)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [061b079f8] 2014-01-14 17:35:21 -0500
Branch: REL9_3_STABLE [ebde6c401] 2014-01-14 17:34:51 -0500
Branch: REL9_2_STABLE [ad2e041a3] 2014-01-14 17:34:54 -0500
Branch: REL9_1_STABLE [ab4bb5c47] 2014-01-14 17:34:57 -0500
Branch: REL9_0_STABLE [5d742b9ce] 2014-01-14 17:35:00 -0500
-->

    <listitem>
     <para>
      Fix improper locking of btree index pages while replaying
      a <literal>VACUUM</literal> operation in hot-standby mode (Andres Freund,
      Heikki Linnakangas, Tom Lane)
     </para>

     <para>
      This error could result in <quote>PANIC: WAL contains references to
      invalid pages</quote> failures.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [22122c83f] 2013-12-03 23:16:01 +0200
Branch: REL9_3_STABLE [8fd04cb32] 2013-12-03 22:13:16 +0200
Branch: REL9_2_STABLE [06df57ac6] 2013-12-03 22:34:31 +0200
Branch: REL9_1_STABLE [e6acb956a] 2013-12-03 22:34:43 +0200
Branch: REL9_0_STABLE [760606dc5] 2013-12-03 23:01:31 +0200
Branch: REL8_4_STABLE [67fc33d3a] 2013-12-03 22:53:26 +0200
-->

    <listitem>
     <para>
      Ensure that insertions into non-leaf GIN index pages write a full-page
      WAL record when appropriate (Heikki Linnakangas)
     </para>

     <para>
      The previous coding risked index corruption in the event of a
      partial-page write during a system crash.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [3739e5ab9] 2014-01-08 23:28:52 +0200
Branch: REL9_3_STABLE [3aefff422] 2014-01-08 23:30:46 +0200
Branch: REL9_2_STABLE [3bd8987ef] 2014-01-08 23:30:55 +0200
Branch: REL9_1_STABLE [0402f2441] 2014-01-08 23:31:01 +0200
-->

    <listitem>
     <para>
      When <literal>pause_at_recovery_target</literal>
      and <literal>recovery_target_inclusive</literal> are both set, ensure the
      target record is applied before pausing, not after (Heikki
      Linnakangas)
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [a472ae1e4] 2014-01-16 23:15:41 +0200
Branch: REL9_3_STABLE [e34acac62] 2014-01-16 23:14:57 +0200
-->

    <listitem>
     <para>
      Ensure walreceiver sends hot-standby feedback messages on time even
      when there is a continuous stream of data (Andres Freund, Amit
      Kapila)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [e8312b4f0] 2013-12-13 11:50:15 -0500
Branch: REL9_3_STABLE [478af9b79] 2013-12-13 11:50:25 -0500
-->

    <listitem>
     <para>
      Prevent timeout interrupts from taking control away from mainline
      code unless <varname>ImmediateInterruptOK</varname> is set
      (Andres Freund, Tom Lane)
     </para>

     <para>
      This is a serious issue for any application making use of statement
      timeouts, as it could cause all manner of strange failures after a
      timeout occurred.  We have seen reports of <quote>stuck</quote> spinlocks,
      ERRORs being unexpectedly promoted to PANICs, unkillable backends,
      and other misbehaviors.
     </para>
    </listitem>

<!--
Author: Robert Haas <rhaas@postgresql.org>
Branch: master [d1981719a] 2014-01-31 21:31:08 -0500
Branch: REL9_3_STABLE [5d807a74b] 2014-01-31 21:34:44 -0500
Branch: REL9_2_STABLE [ebe334463] 2014-01-31 21:35:32 -0500
Branch: REL9_1_STABLE [8e6bfc9eb] 2014-01-31 21:36:23 -0500
Branch: REL9_0_STABLE [798243a81] 2014-01-31 21:40:20 -0500
Branch: REL8_4_STABLE [458b20f2d] 2014-01-31 21:41:09 -0500
-->

    <listitem>
     <para>
      Fix race conditions during server process exit (Robert Haas)
     </para>

     <para>
      Ensure that signal handlers don't attempt to use the
      process's <varname>MyProc</varname> pointer after it's no longer valid.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [214c7a4f0] 2014-02-01 16:21:23 -0500
Branch: REL9_3_STABLE [6f1a40773] 2014-02-01 16:21:30 -0500
Branch: REL9_2_STABLE [81b116d98] 2014-02-01 16:21:33 -0500
Branch: REL9_1_STABLE [03f06ff38] 2014-02-01 16:21:38 -0500
-->

    <listitem>
     <para>
      Fix race conditions in walsender shutdown logic and walreceiver
      SIGHUP signal handler (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [571addd72] 2014-01-29 20:04:43 -0500
Branch: REL9_3_STABLE [bf8ee6f15] 2014-01-29 20:04:01 -0500
Branch: REL9_2_STABLE [3e71ce1e9] 2014-01-29 20:04:05 -0500
Branch: REL9_1_STABLE [af259c691] 2014-01-29 20:04:08 -0500
Branch: REL9_0_STABLE [d17a667e8] 2014-01-29 20:04:11 -0500
Branch: REL8_4_STABLE [01b882fd8] 2014-01-29 20:04:14 -0500
-->

    <listitem>
     <para>
      Fix unsafe references to <varname>errno</varname> within error reporting
      logic (Christian Kruse)
     </para>

     <para>
      This would typically lead to odd behaviors such as missing or
      inappropriate <literal>HINT</literal> fields.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [910bac595] 2014-01-11 16:36:07 -0500
Branch: REL9_3_STABLE [5bfcc9ec5] 2014-01-11 16:35:30 -0500
Branch: REL9_2_STABLE [2de905186] 2014-01-11 16:35:34 -0500
Branch: REL9_1_STABLE [3f721588a] 2014-01-11 16:35:37 -0500
Branch: REL9_0_STABLE [d9c4442b8] 2014-01-11 16:35:41 -0500
Branch: REL8_4_STABLE [d0070ac81] 2014-01-11 16:35:44 -0500
-->

    <listitem>
     <para>
      Fix possible crashes from using <function>ereport()</function> too early
      during server startup (Tom Lane)
     </para>

     <para>
      The principal case we've seen in the field is a crash if the server
      is started in a directory it doesn't have permission to read.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [74242c23c] 2013-12-05 12:48:28 -0500
Branch: REL9_3_STABLE [2a6e1a554] 2013-12-05 12:48:31 -0500
Branch: REL9_2_STABLE [41042970b] 2013-12-05 12:48:35 -0500
Branch: REL9_1_STABLE [ad910ccdc] 2013-12-05 12:48:37 -0500
Branch: REL9_0_STABLE [36352ceb4] 2013-12-05 12:48:41 -0500
Branch: REL8_4_STABLE [7635dae55] 2013-12-05 12:48:44 -0500
-->

    <listitem>
     <para>
      Clear retry flags properly in OpenSSL socket write
      function (Alexander Kukushkin)
     </para>

     <para>
      This omission could result in a server lockup after unexpected loss
      of an SSL-encrypted connection.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [44c216330] 2014-02-13 14:24:42 -0500
Branch: REL9_3_STABLE [ca1c17181] 2014-02-13 14:24:45 -0500
Branch: REL9_2_STABLE [8439ee415] 2014-02-13 14:24:49 -0500
Branch: REL9_1_STABLE [170590261] 2014-02-13 14:24:52 -0500
Branch: REL9_0_STABLE [148052d25] 2014-02-13 14:24:55 -0500
Branch: REL8_4_STABLE [a8a46d846] 2014-02-13 14:24:58 -0500
-->

    <listitem>
     <para>
      Fix length checking for Unicode identifiers (<literal>U&amp;"..."</literal>
      syntax) containing escapes (Tom Lane)
     </para>

     <para>
      A spurious truncation warning would be printed for such identifiers
      if the escaped form of the identifier was too long, but the
      identifier actually didn't need truncation after de-escaping.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [0c2338abb] 2014-02-03 19:47:57 -0500
Branch: REL9_3_STABLE [4c70cb1d3] 2014-02-03 19:48:00 -0500
-->

    <listitem>
     <para>
      Fix parsing of Unicode literals and identifiers just before the end
      of a command string or function body (Tom Lane)
     </para>
    </listitem>

<!--
Author: Stephen Frost <sfrost@snowman.net>
Branch: master [6c36f383d] 2014-01-21 22:49:22 -0500
Branch: REL9_3_STABLE [d1e3070f0] 2014-01-21 22:56:30 -0500
Branch: REL9_2_STABLE [c0e6169e1] 2014-01-21 22:56:34 -0500
Branch: REL9_1_STABLE [cbd850bf6] 2014-01-21 23:00:58 -0500
Branch: REL9_0_STABLE [f2eede9b5] 2014-01-21 23:01:40 -0500
-->

    <listitem>
     <para>
      Allow keywords that are type names to be used in lists of roles
      (Stephen Frost)
     </para>

     <para>
      A previous patch allowed such keywords to be used without quoting
      in places such as role identifiers; but it missed cases where a
      list of role identifiers was permitted, such as <literal>DROP ROLE</literal>.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [7ab321404] 2013-12-02 20:28:45 -0500
Branch: REL9_3_STABLE [b44ae4893] 2013-12-02 20:28:49 -0500
Branch: REL9_2_STABLE [6698782f1] 2013-12-02 20:28:53 -0500
Branch: REL9_1_STABLE [f67b8aeab] 2013-12-02 20:28:56 -0500
-->

    <listitem>
     <para>
      Fix parser crash for <literal>EXISTS(SELECT * FROM
      zero_column_table)</literal> (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [9ec6199d1] 2013-12-10 16:10:17 -0500
Branch: REL9_3_STABLE [9d2e07fec] 2013-12-10 16:10:20 -0500
Branch: REL9_2_STABLE [f5d9fdcc7] 2013-12-10 16:10:24 -0500
Branch: REL9_1_STABLE [48e5cfde8] 2013-12-10 16:10:28 -0500
Branch: REL9_0_STABLE [41e9990cd] 2013-12-10 16:10:31 -0500
Branch: REL8_4_STABLE [884c6384a] 2013-12-10 16:10:36 -0500
-->

    <listitem>
     <para>
      Fix possible crash due to invalid plan for nested sub-selects, such
      as <literal>WHERE (... x IN (SELECT ...) ...) IN (SELECT ...)</literal>
      (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [043f6ff05] 2014-01-30 14:51:16 -0500
Branch: REL9_3_STABLE [a4aa854ca] 2014-01-30 14:51:19 -0500
-->

    <listitem>
     <para>
      Fix mishandling of <literal>WHERE</literal> conditions pulled up from
      a <literal>LATERAL</literal> subquery (Tom Lane)
     </para>

     <para>
      The typical symptom of this bug was a <quote>JOIN qualification
      cannot refer to other relations</quote> error, though subtle logic
      errors in created plans seem possible as well.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [158b7fa6a] 2014-01-11 19:03:12 -0500
Branch: REL9_3_STABLE [27ff4cfe7] 2014-01-11 19:03:15 -0500
-->

    <listitem>
     <para>
      Disallow <literal>LATERAL</literal> references to the target table of
      an <literal>UPDATE/DELETE</literal> (Tom Lane)
     </para>

     <para>
      While this might be allowed in some future release, it was
      unintentional in 9.3, and didn't work quite right anyway.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [c03ad5602] 2013-12-14 17:33:53 -0500
Branch: REL9_3_STABLE [324577f39] 2013-12-14 17:33:56 -0500
Branch: REL9_2_STABLE [5d545b7ed] 2013-12-14 17:34:00 -0500
-->

    <listitem>
     <para>
      Fix <literal>UPDATE/DELETE</literal> of an inherited target table
      that has <literal>UNION ALL</literal> subqueries (Tom Lane)
     </para>

     <para>
      Without this fix, <literal>UNION ALL</literal> subqueries aren't correctly
      inserted into the update plans for inheritance child tables after the
      first one, typically resulting in no update happening for those child
      table(s).
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [4eeda92d8] 2013-12-23 22:18:48 -0500
Branch: REL9_3_STABLE [663f8419b] 2013-12-23 22:18:23 -0500
-->

    <listitem>
     <para>
      Fix <command>ANALYZE</command> to not fail on a column that's a domain over
      a range type (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [628652620] 2014-01-11 13:42:42 -0500
Branch: REL9_3_STABLE [36785a21b] 2014-01-11 13:41:51 -0500
Branch: REL9_2_STABLE [f0381680f] 2014-01-11 13:41:56 -0500
Branch: REL9_1_STABLE [9387f4e1b] 2014-01-11 13:42:00 -0500
Branch: REL9_0_STABLE [2d76d75d9] 2014-01-11 13:42:05 -0500
Branch: REL8_4_STABLE [00b77771a] 2014-01-11 13:42:11 -0500
-->

    <listitem>
     <para>
      Ensure that <command>ANALYZE</command> creates statistics for a table column
      even when all the values in it are <quote>too wide</quote> (Tom Lane)
     </para>

     <para>
      <command>ANALYZE</command> intentionally omits very wide values from its
      histogram and most-common-values calculations, but it neglected to do
      something sane in the case that all the sampled entries are too wide.
     </para>
    </listitem>

<!--
Author: Stephen Frost <sfrost@snowman.net>
Branch: master [6f25c62d7] 2014-01-18 18:41:52 -0500
Branch: REL9_3_STABLE [86e58ae02] 2014-01-18 18:49:08 -0500
Branch: REL9_2_STABLE [1fe06595a] 2014-01-18 18:49:41 -0500
Branch: REL9_1_STABLE [d2636486b] 2014-01-18 18:50:09 -0500
Branch: REL9_0_STABLE [e70c42821] 2014-01-18 18:50:29 -0500
Branch: REL8_4_STABLE [0fb4e3ceb] 2014-01-18 18:50:47 -0500
-->

    <listitem>
     <para>
      In <literal>ALTER TABLE ... SET TABLESPACE</literal>, allow the database's
      default tablespace to be used without a permissions check
      (Stephen Frost)
     </para>

     <para>
      <literal>CREATE TABLE</literal> has always allowed such usage,
      but <literal>ALTER TABLE</literal> didn't get the memo.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [c01bc51f8] 2013-12-30 14:00:02 -0500
Branch: REL9_3_STABLE [9a6e2b150] 2013-12-30 14:00:05 -0500
-->

    <listitem>
     <para>
      Fix support for extensions containing event triggers (Tom Lane)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [080b7db72] 2014-01-08 20:18:58 -0500
Branch: REL9_3_STABLE [47ac4473a] 2014-01-08 20:18:10 -0500
Branch: REL9_2_STABLE [97a39f295] 2014-01-08 20:18:13 -0500
Branch: REL9_1_STABLE [6c6c53d0b] 2014-01-08 20:18:17 -0500
Branch: REL9_0_STABLE [6ca712fb9] 2014-01-08 20:18:20 -0500
Branch: REL8_4_STABLE [57ac7d8a7] 2014-01-08 20:18:24 -0500
-->

    <listitem>
     <para>
      Fix <quote>cannot accept a set</quote> error when some arms of
      a <literal>CASE</literal> return a set and others don't (Tom Lane)
     </para>
    </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
Branch: master [d3ee45152] 2014-02-03 10:40:12 -0500
Branch: REL9_3_STABLE [cdfbb78f0] 2014-02-03 10:39:13 -0500
-->

    <listitem>
     <para>
      Fix memory leakage in JSON functions (Craig Ringer)
     </para>
    </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
Branch: master [29dcf7ded] 2013-12-27 17:04:00 -0500
Branch: REL9_3_STABLE [7dfd9f6f5] 2013-12-27 17:21:04 -0500
Branch: REL9_2_STABLE [4825a9e95] 2013-12-27 17:21:27 -0500
-->

    <listitem>
     <para>
      Properly distinguish numbers from non-numbers when generating JSON
      output (Andrew Dunstan)
     </para>
    </listitem>

<!--
Author: Kevin Grittner <kgrittn@postgresql.org>
Branch: master [a133bf703] 2013-12-27 15:26:24 -0600
Branch: REL9_3_STABLE [28b60aa23] 2013-12-27 15:40:51 -0600
Branch: REL9_2_STABLE [150a30e19] 2013-12-27 15:41:02 -0600
Branch: REL9_1_STABLE [1f069d21d] 2013-12-27 15:41:18 -0600
Branch: REL9_0_STABLE [918d74a07] 2013-12-27 15:41:32 -0600
Branch: REL8_4_STABLE [b2d80147d] 2013-12-27 15:41:46 -0600
-->

    <listitem>
     <para>
      Fix checks for all-zero client addresses in pgstat functions (Kevin
      Grittner)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [082c0dfa1] 2014-02-01 18:27:34 -0500
Branch: REL9_3_STABLE [9beffdcc3] 2014-02-01 18:27:40 -0500
Branch: REL9_2_STABLE [8be095cea] 2014-02-01 18:27:44 -0500
Branch: REL9_1_STABLE [399d23e19] 2014-02-01 18:27:48 -0500
Branch: REL9_0_STABLE [3c7b4ef70] 2014-02-01 18:27:54 -0500
Branch: REL8_4_STABLE [56f5d3424] 2014-02-01 18:27:12 -0500
-->

    <listitem>
     <para>
      Fix possible misclassification of multibyte characters by the text
      search parser (Tom Lane)
     </para>

     <para>
      Non-ASCII characters could be misclassified when using C locale with
      a multibyte encoding.  On Cygwin, non-C locales could fail as well.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [6c2744f1d] 2014-02-10 09:57:59 +0200
Branch: REL9_3_STABLE [928aec71c] 2014-02-10 09:59:49 +0200
Branch: REL9_2_STABLE [f3807106b] 2014-02-10 10:00:04 +0200
Branch: REL9_1_STABLE [5f778e644] 2014-02-10 10:00:23 +0200
Branch: REL9_0_STABLE [fe8a6f53e] 2014-02-10 10:00:36 +0200
Branch: REL8_4_STABLE [6141983fb] 2014-02-10 10:00:50 +0200
-->

    <listitem>
     <para>
      Fix possible misbehavior in <function>plainto_tsquery()</function>
      (Heikki Linnakangas)
     </para>

     <para>
      Use <function>memmove()</function> not <function>memcpy()</function> for copying
      overlapping memory regions.  There have been no field reports of
      this actually causing trouble, but it's certainly risky.
     </para>
    </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
Branch: master [9544cc0d6] 2014-01-07 17:50:56 +0100
Branch: REL9_3_STABLE [91c2755fc] 2014-01-07 17:51:02 +0100
Branch: REL9_2_STABLE [61d4d14ee] 2014-01-07 17:53:00 +0100
Branch: REL9_1_STABLE [026a91f86] 2014-01-07 18:00:36 +0100
-->

    <listitem>
     <para>
      Fix placement of permissions checks in <function>pg_start_backup()</function>
      and <function>pg_stop_backup()</function> (Andres Freund, Magnus Hagander)
     </para>

     <para>
      The previous coding might attempt to do catalog access when it
      shouldn't.
     </para>
    </listitem>

<!--
Author: Tatsuo Ishii <ishii@postgresql.org>
Branch: master [1f0626ee4] 2013-12-15 11:09:05 +0900
Branch: REL9_3_STABLE [8122e6f85] 2013-12-15 11:10:41 +0900
Branch: REL9_2_STABLE [0c07ef1ad] 2013-12-15 11:10:49 +0900
Branch: REL9_1_STABLE [035226c61] 2013-12-15 11:10:56 +0900
Branch: REL9_0_STABLE [7016d970d] 2013-12-15 11:11:02 +0900
Branch: REL8_4_STABLE [69f77d756] 2013-12-15 11:11:11 +0900
-->

    <listitem>
     <para>
      Accept <literal>SHIFT_JIS</literal> as an encoding name for locale checking
      purposes (Tatsuo Ishii)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [0def2573c] 2014-02-03 14:47:17 -0500
Branch: REL9_3_STABLE [641c08041] 2014-02-03 14:46:54 -0500
Branch: REL9_2_STABLE [888b56570] 2014-02-03 14:46:57 -0500
-->

    <listitem>
     <para>
      Fix <literal>*</literal>-qualification of named parameters in SQL-language
      functions (Tom Lane)
     </para>

     <para>
      Given a composite-type parameter
      named <literal>foo</literal>, <literal>$1.*</literal> worked fine,
      but <literal>foo.*</literal> not so much.
     </para>
    </listitem>

<!--
Author: Fujii Masao <fujii@postgresql.org>
Branch: master [77035fa8a] 2014-01-23 22:58:58 +0900
Branch: REL9_3_STABLE [be5d49974] 2014-01-23 23:00:30 +0900
Branch: REL9_2_STABLE [ea311bfdf] 2014-01-23 23:01:06 +0900
Branch: REL9_1_STABLE [1b384aff1] 2014-01-23 23:01:34 +0900
Branch: REL9_0_STABLE [996b21cbf] 2014-01-23 23:02:03 +0900
Branch: REL8_4_STABLE [5525529db] 2014-01-23 23:02:30 +0900
-->

    <listitem>
     <para>
      Fix misbehavior of <function>PQhost()</function> on Windows (Fujii Masao)
     </para>

     <para>
      It should return <literal>localhost</literal> if no host has been specified.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [b8f00a46b] 2014-02-13 18:45:58 -0500
Branch: REL9_3_STABLE [f208fb436] 2014-02-13 18:46:03 -0500
Branch: REL9_2_STABLE [2573f08a1] 2014-02-13 18:45:20 -0500
Branch: REL9_1_STABLE [7182bd239] 2014-02-13 18:45:23 -0500
Branch: REL9_0_STABLE [218dd205b] 2014-02-13 18:45:27 -0500
Branch: REL8_4_STABLE [7644a7bd8] 2014-02-13 18:45:32 -0500
-->

    <listitem>
     <para>
      Improve error handling in <application>libpq</application> and <application>psql</application>
      for failures during <literal>COPY TO STDOUT/FROM STDIN</literal> (Tom Lane)
     </para>

     <para>
      In particular this fixes an infinite loop that could occur in 9.2 and
      up if the server connection was lost during <literal>COPY FROM
      STDIN</literal>.  Variants of that scenario might be possible in older
      versions, or with other client applications.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [92459e7a7] 2014-01-04 16:05:16 -0500
Branch: REL9_3_STABLE [341f0bc49] 2014-01-04 16:05:20 -0500
Branch: REL9_2_STABLE [fa28f9cba] 2014-01-04 16:05:23 -0500
-->

    <listitem>
     <para>
      Fix incorrect translation handling in
      some <application>psql</application> <literal>\d</literal> commands
      (Peter Eisentraut, Tom Lane)
     </para>
    </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
Branch: master [63ab2befe] 2014-02-12 18:45:18 +0100
Branch: REL9_3_STABLE [c90204c60] 2014-02-12 18:46:04 +0100
Branch: REL9_2_STABLE [0ae288d2d] 2014-02-12 14:51:00 +0100
-->

    <listitem>
     <para>
      Ensure <application>pg_basebackup</application>'s background process is killed
      when exiting its foreground process (Magnus Hagander)
     </para>
    </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
Branch: master [01025d80a] 2014-02-09 12:05:14 +0100
Branch: REL9_3_STABLE [680baa8d2] 2014-02-09 12:09:18 +0100
Branch: REL9_2_STABLE [165aa1da5] 2014-02-09 12:09:39 +0100
Branch: REL9_1_STABLE [c6e5c4dd1] 2014-02-09 12:09:55 +0100
-->

    <listitem>
     <para>
      Fix possible incorrect printing of filenames
      in <application>pg_basebackup</application>'s verbose mode (Magnus Hagander)
     </para>
    </listitem>

<!--
Author: Magnus Hagander <magnus@hagander.net>
Branch: master [b168c5ef2] 2014-01-07 17:11:32 +0100
Branch: REL9_3_STABLE [0463b9419] 2014-01-07 17:11:51 +0100
Branch: REL9_2_STABLE [2edf3e82c] 2014-01-07 17:22:36 +0100
Branch: REL9_1_STABLE [773e4d5e4] 2014-01-07 17:18:02 +0100
-->

    <listitem>
     <para>
      Avoid including tablespaces inside PGDATA twice in base backups
      (Dimitri Fontaine, Magnus Hagander)
     </para>
    </listitem>

<!--
Author: Michael Meskes <meskes@postgresql.org>
Branch: master [d685e2424] 2014-01-09 16:20:19 +0100
Branch: REL9_3_STABLE [28fff0ef8] 2014-01-09 15:41:51 +0100
Branch: REL9_2_STABLE [799728b0b] 2014-01-09 15:50:51 +0100
Branch: REL9_1_STABLE [9f5b3a1a1] 2014-01-09 15:51:11 +0100
Branch: REL9_0_STABLE [a29b6c342] 2014-01-09 15:51:23 +0100
Branch: REL8_4_STABLE [d68a65b01] 2014-01-09 15:58:37 +0100
-->

    <listitem>
     <para>
      Fix misaligned descriptors in <application>ecpg</application> (MauMau)
     </para>
    </listitem>

<!--
Author: Michael Meskes <meskes@postgresql.org>
Branch: master [7c957ec83] 2014-01-01 12:39:31 +0100
Branch: REL9_3_STABLE [8404037d8] 2014-01-01 12:40:28 +0100
Branch: REL9_2_STABLE [119a59879] 2014-01-01 12:40:42 +0100
Branch: REL9_1_STABLE [948498274] 2014-01-01 12:44:15 +0100
Branch: REL9_0_STABLE [17bcdd01f] 2014-01-01 12:44:44 +0100
Branch: REL8_4_STABLE [96de4939c] 2014-01-01 12:44:58 +0100
-->

    <listitem>
     <para>
      In <application>ecpg</application>, handle lack of a hostname in the connection
      parameters properly (Michael Meskes)
     </para>
    </listitem>

<!--
Author: Joe Conway <mail@joeconway.com>
Branch: master [d6ca510d9] 2013-12-07 17:00:26 -0800
Branch: REL9_3_STABLE [0ec530625] 2013-12-07 17:00:10 -0800
Branch: REL9_2_STABLE [7f4ef622f] 2013-12-07 16:59:35 -0800
Branch: REL9_1_STABLE [70165f25b] 2013-12-07 16:59:16 -0800
Branch: REL9_0_STABLE [9057adc23] 2013-12-07 16:58:41 -0800
Branch: REL8_4_STABLE [6c8b16e30] 2013-12-07 16:56:34 -0800
-->

    <listitem>
     <para>
      Fix performance regression in <filename>contrib/dblink</filename> connection
      startup (Joe Conway)
     </para>

     <para>
      Avoid an unnecessary round trip when client and server encodings match.
     </para>
    </listitem>

<!--
Author: Heikki Linnakangas <heikki.linnakangas@iki.fi>
Branch: master [866a1f092] 2014-01-13 15:43:29 +0200
Branch: REL9_3_STABLE [50c5770ec] 2014-01-13 15:43:59 +0200
Branch: REL9_2_STABLE [f6d6b42f2] 2014-01-13 15:44:02 +0200
Branch: REL9_1_STABLE [5143dfd57] 2014-01-13 15:44:04 +0200
Branch: REL9_0_STABLE [6c3f040be] 2014-01-13 15:44:12 +0200
Branch: REL8_4_STABLE [492b68541] 2014-01-13 15:44:14 +0200
-->

    <listitem>
     <para>
      In <filename>contrib/isn</filename>, fix incorrect calculation of the check
      digit for ISMN values (Fabien Coelho)
     </para>
    </listitem>

<!--
Author: Tatsuo Ishii <ishii@postgresql.org>
Branch: master [841a65482] 2013-12-12 19:10:35 +0900
Branch: REL9_3_STABLE [27902bc91] 2013-12-12 19:07:53 +0900
-->

    <listitem>
     <para>
      Fix <filename>contrib/pgbench</filename>'s progress logging to avoid overflow
      when the scale factor is large (Tatsuo Ishii)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [69c7a9838] 2014-01-21 16:34:28 -0500
Branch: REL9_3_STABLE [0950d67ee] 2014-01-21 16:34:31 -0500
Branch: REL9_2_STABLE [27ab1eb7e] 2014-01-21 16:34:35 -0500
-->

    <listitem>
     <para>
      Fix <filename>contrib/pg_stat_statement</filename>'s handling
      of <literal>CURRENT_DATE</literal> and related constructs (Kyotaro
      Horiguchi)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [00d4f2af8] 2014-02-03 21:30:20 -0500
Branch: REL9_3_STABLE [eb3d350db] 2014-02-03 21:30:28 -0500
-->

    <listitem>
     <para>
      Improve lost-connection error handling
      in <filename>contrib/postgres_fdw</filename> (Tom Lane)
     </para>
    </listitem>

<!--
Author: Peter Eisentraut <peter_e@gmx.net>
Branch: master [ad6bf0291] 2014-01-17 23:08:22 -0500
Branch: REL9_3_STABLE [586bea612] 2014-01-17 23:11:02 -0500
Branch: REL9_2_STABLE [526e38751] 2014-01-17 23:12:50 -0500
Branch: REL9_1_STABLE [6d969b000] 2014-01-17 23:14:21 -0500
Branch: REL9_0_STABLE [2346c383a] 2014-01-17 23:15:00 -0500
Branch: REL8_4_STABLE [15699d9bf] 2014-01-17 23:17:59 -0500
-->

    <listitem>
     <para>
      Ensure client-code-only installation procedure works as documented
      (Peter Eisentraut)
     </para>
    </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
Branch: master [d587298b8] 2014-02-01 15:11:13 -0500
Branch: REL9_3_STABLE [1e9876c3b] 2014-02-01 15:16:06 -0500
Branch: REL9_2_STABLE [6e96d4db8] 2014-02-01 15:16:18 -0500
Branch: REL9_1_STABLE [dfb4a1a21] 2014-02-01 15:16:29 -0500
Branch: REL9_0_STABLE [59d64e7f3] 2014-02-01 15:16:40 -0500
Branch: REL8_4_STABLE [ae3c98b9b] 2014-02-01 15:16:52 -0500
-->

    <listitem>
     <para>
      In Mingw and Cygwin builds, install the <application>libpq</application> DLL
      in the <filename>bin</filename> directory (Andrew Dunstan)
     </para>

     <para>
      This duplicates what the MSVC build has long done.  It should fix
      problems with programs like <application>psql</application> failing to start
      because they can't find the DLL.
     </para>
    </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
Branch: master [7e1531a45] 2014-02-01 16:08:33 -0500
Branch: REL9_3_STABLE [27942baf4] 2014-02-01 16:13:32 -0500
Branch: REL9_2_STABLE [fad443753] 2014-02-01 16:13:46 -0500
Branch: REL9_1_STABLE [e5c22c15d] 2014-02-01 16:14:01 -0500
Branch: REL9_0_STABLE [1c0bf372f] 2014-02-01 16:14:15 -0500
-->

    <listitem>
     <para>
      Avoid using the deprecated <literal>dllwrap</literal> tool in Cygwin builds
      (Marco Atzeri)
     </para>
    </listitem>

<!--
Author: Andrew Dunstan <andrew@dunslane.net>
Branch: master [cec8394b5] 2014-01-26 09:49:10 -0500
Branch: REL9_3_STABLE [56c08df55] 2014-01-26 09:45:43 -0500
-->

    <listitem>
     <para>
      Enable building with Visual Studio 2013 (Brar Piening)
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [289541520] 2014-02-10 20:48:04 -0500
Branch: REL9_3_STABLE [f1e522696] 2014-02-10 20:48:12 -0500
Branch: REL9_2_STABLE [dd5605104] 2014-02-10 20:48:20 -0500
Branch: REL9_1_STABLE [3bf5c16f1] 2014-02-10 20:48:23 -0500
Branch: REL9_0_STABLE [e1e7642bd] 2014-02-10 20:48:27 -0500
Branch: REL8_4_STABLE [432735cbf] 2014-02-10 20:48:30 -0500
-->

    <listitem>
     <para>
      Don't generate plain-text <filename>HISTORY</filename>
      and <filename>src/test/regress/README</filename> files anymore (Tom Lane)
     </para>

     <para>
      These text files duplicated the main HTML and PDF documentation
      formats.  The trouble involved in maintaining them greatly outweighs
      the likely audience for plain-text format.  Distribution tarballs
      will still contain files by these names, but they'll just be stubs
      directing the reader to consult the main documentation.
      The plain-text <filename>INSTALL</filename> file will still be maintained, as
      there is arguably a use-case for that.
     </para>
    </listitem>

<!--
Author: Tom Lane <tgl@sss.pgh.pa.us>
Branch: master [e04641f4b] 2014-02-14 21:59:13 -0500
Branch: REL9_3_STABLE [46cbcd50e] 2014-02-14 21:59:37 -0500
Branch: REL9_2_STABLE [4f975b68b] 2014-02-14 21:59:42 -0500
Branch: REL9_1_STABLE [3212ba534] 2014-02-14 21:59:46 -0500
Branch: REL9_0_STABLE [cb84fddd9] 2014-02-14 21:59:50 -0500
Branch: REL8_4_STABLE [c0c2d62ac] 2014-02-14 21:59:56 -0500
-->

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2013i
      for DST law changes in Jordan and historical changes in Cuba.
     </para>

     <para>
      In addition, the zones <literal>Asia/Riyadh87</literal>,
      <literal>Asia/Riyadh88</literal>, and <literal>Asia/Riyadh89</literal> have been
      removed, as they are no longer maintained by IANA, and never
      represented actual civil timekeeping practice.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-2">
  <title>Release 9.3.2</title>

  <formalpara>
  <title>Release date:</title>
  <para>2013-12-05</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.1.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.2</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, this release corrects a number of potential data corruption
    issues.  See the first three changelog entries below to find out whether
    your installation has been affected and what steps you can take if so.
   </para>

   <para>
    Also, if you are upgrading from a version earlier than 9.3.1,
    see <xref linkend="release-9-3-1"/>.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Fix <command>VACUUM</command>'s tests to see whether it can
      update <structfield>relfrozenxid</structfield> (Andres Freund)
     </para>

     <para>
      In some cases <command>VACUUM</command> (either manual or autovacuum) could
      incorrectly advance a table's <structfield>relfrozenxid</structfield> value,
      allowing tuples to escape freezing, causing those rows to become
      invisible once 2^31 transactions have elapsed.  The probability of
      data loss is fairly low since multiple incorrect advancements would
      need to happen before actual loss occurs, but it's not zero.  In 9.2.0
      and later, the probability of loss is higher, and it's also possible
      to get <quote>could not access status of transaction</quote> errors as a
      consequence of this bug.  Users upgrading from releases 9.0.4 or 8.4.8
      or earlier are not affected, but all later versions contain the bug.
     </para>

     <para>
      The issue can be ameliorated by, after upgrading, vacuuming all tables
      in all databases while having <link
      linkend="guc-vacuum-freeze-table-age"><varname>vacuum_freeze_table_age</varname></link>
      set to zero.  This will fix any latent corruption but will not be able
      to fix all pre-existing data errors.  However, an installation can be
      presumed safe after performing this vacuuming if it has executed fewer
      than 2^31 update transactions in its lifetime (check this with
      <literal>SELECT txid_current() &lt; 2^31</literal>).
     </para>
    </listitem>

    <listitem>
     <para>
      Fix multiple bugs in MultiXactId freezing (Andres Freund,
      &Aacute;lvaro Herrera)
     </para>

     <para>
      These bugs could lead to <quote>could not access status of
      transaction</quote> errors, or to duplicate or vanishing rows.
      Users upgrading from releases prior to 9.3.0 are not affected.
     </para>

     <para>
      The issue can be ameliorated by, after upgrading, vacuuming all tables
      in all databases while having <link
      linkend="guc-vacuum-freeze-table-age"><varname>vacuum_freeze_table_age</varname></link>
      set to zero.  This will fix latent corruption but will not be able to
      fix all pre-existing data errors.
     </para>

     <para>
      As a separate issue, these bugs can also cause standby servers to get
      out of sync with the primary, thus exhibiting data errors that are not
      in the primary.  Therefore, it's recommended that 9.3.0 and 9.3.1
      standby servers be re-cloned from the primary (e.g., with a new base
      backup) after upgrading.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix initialization of <filename>pg_clog</filename> and <filename>pg_subtrans</filename>
      during hot standby startup (Andres Freund, Heikki Linnakangas)
     </para>

     <para>
      This bug can cause data loss on standby servers at the moment they
      start to accept hot-standby queries, by marking committed transactions
      as uncommitted. The likelihood of such corruption is small unless, at
      the time of standby startup, the primary server has executed many
      updating transactions since its last checkpoint.  Symptoms include
      missing rows, rows that should have been deleted being still visible,
      and obsolete versions of updated rows being still visible alongside
      their newer versions.
     </para>

     <para>
      This bug was introduced in versions 9.3.0, 9.2.5, 9.1.10, and 9.0.14.
      Standby servers that have only been running earlier releases are not
      at risk.  It's recommended that standby servers that have ever run any
      of the buggy releases be re-cloned from the primary (e.g., with a new
      base backup) after upgrading.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix multiple bugs in update chain traversal (Andres Freund,
      &Aacute;lvaro Herrera)
     </para>

     <para>
      These bugs could result in incorrect behavior, such as locking or even
      updating the wrong row, in the presence of concurrent updates.
      Spurious <quote>unable to fetch updated version of tuple</quote> errors
      were also possible.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix dangling-pointer problem in fast-path locking (Tom Lane)
     </para>

     <para>
      This could lead to corruption of the lock data structures in shared
      memory, causing <quote>lock already held</quote> and other odd errors.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix assorted race conditions in timeout management (Tom Lane)
     </para>

     <para>
      These errors could result in a server process becoming unresponsive
      because it had blocked SIGALRM and/or SIGINT.
     </para>
    </listitem>

    <listitem>
     <para>
      Truncate <filename>pg_multixact</filename> contents during WAL replay
      (Andres Freund)
     </para>

     <para>
      This avoids ever-increasing disk space consumption in standby servers.
     </para>
    </listitem>

    <listitem>
     <para>
      Ensure an anti-wraparound <command>VACUUM</command> counts a page as scanned
      when it's only verified that no tuples need freezing (Sergey
      Burladyan, Jeff Janes)
     </para>

     <para>
      This bug could result in failing to
      advance <structfield>relfrozenxid</structfield>, so that the table would still be
      thought to need another anti-wraparound vacuum.  In the worst case the
      database might even shut down to prevent wraparound.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix full-table-vacuum request mechanism for MultiXactIds (Andres Freund)
     </para>

     <para>
      This bug could result in large amounts of useless autovacuum activity.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix race condition in GIN index posting tree page deletion (Heikki
      Linnakangas)
     </para>

     <para>
      This could lead to transient wrong answers or query failures.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <quote>unexpected spgdoinsert() failure</quote> error during SP-GiST
      index creation (Teodor Sigaev)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix assorted bugs in materialized views (Kevin Grittner, Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Re-allow duplicate table aliases if they're within aliased JOINs
      (Tom Lane)
     </para>

     <para>
      Historically <productname>PostgreSQL</productname> has accepted queries like
<programlisting>
SELECT ... FROM tab1 x CROSS JOIN (tab2 x CROSS JOIN tab3 y) z
</programlisting>
      although a strict reading of the SQL standard would forbid the
      duplicate usage of table alias <literal>x</literal>.  A misguided change in
      9.3.0 caused it to reject some such cases that were formerly accepted.
      Restore the previous behavior.
     </para>
    </listitem>

    <listitem>
     <para>
      Avoid flattening a subquery whose <literal>SELECT</literal> list contains a
      volatile function wrapped inside a sub-<literal>SELECT</literal> (Tom Lane)
     </para>

     <para>
      This avoids unexpected results due to extra evaluations of the
      volatile function.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix planner's processing of non-simple-variable subquery outputs
      nested within outer joins (Tom Lane)
     </para>

     <para>
      This error could lead to incorrect plans for queries involving
      multiple levels of subqueries within <literal>JOIN</literal> syntax.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect planning in cases where the same non-strict expression
      appears in multiple <literal>WHERE</literal> and outer <literal>JOIN</literal>
      equality clauses (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix planner crash with whole-row reference to a subquery (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect generation of optimized MIN()/MAX() plans for
      inheritance trees (Tom Lane)
     </para>

     <para>
      The planner could fail in cases where the MIN()/MAX() argument was an
      expression rather than a simple variable.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix premature deletion of temporary files (Andres Freund)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent intra-transaction memory leak when printing range values
      (Tom Lane)
     </para>

     <para>
      This fix actually cures transient memory leaks in any datatype output
      function, but range types are the only ones known to have had a
      significant problem.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix memory leaks when reloading configuration files (Heikki
      Linnakangas, Hari Babu)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent incorrect display of dropped columns in NOT NULL and CHECK
      constraint violation messages (Michael Paquier and Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Allow default arguments and named-argument notation for window
      functions (Tom Lane)
     </para>

     <para>
      Previously, these cases were likely to crash.
     </para>
    </listitem>

    <listitem>
     <para>
      Suppress trailing whitespace on each line when pretty-printing rules
      and views (Tom Lane)
     </para>

     <para>
      9.3.0 generated such whitespace in many more cases than previous
      versions did.  To reduce unexpected behavioral changes, suppress
      unnecessary whitespace in all cases.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix possible read past end of memory in rule printing (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix array slicing of <type>int2vector</type> and <type>oidvector</type> values
      (Tom Lane)
     </para>

     <para>
      Expressions of this kind are now implicitly promoted to
      regular <type>int2</type> or <type>oid</type> arrays.
     </para>
    </listitem>

    <listitem>
     <para>
      Return a valid JSON value when converting an empty <type>hstore</type> value
      to <type>json</type>
      (Oskari Saarenmaa)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix incorrect behaviors when using a SQL-standard, simple GMT offset
      timezone (Tom Lane)
     </para>

     <para>
      In some cases, the system would use the simple GMT offset value when
      it should have used the regular timezone setting that had prevailed
      before the simple offset was selected.  This change also causes
      the <function>timeofday</function> function to honor the simple GMT offset
      zone.
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent possible misbehavior when logging translations of Windows
      error codes (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Properly quote generated command lines in <application>pg_ctl</application>
      (Naoya Anzai and Tom Lane)
     </para>

     <para>
      This fix applies only to Windows.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_dumpall</application> to work when a source database
      sets <link
      linkend="guc-default-transaction-read-only"><varname>default_transaction_read_only</varname></link>
      via <command>ALTER DATABASE SET</command> (Kevin Grittner)
     </para>

     <para>
      Previously, the generated script would fail during restore.
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>pg_isready</application> to handle its <option>-d</option> option
      properly (Fabr&iacute;zio de Royes Mello and Fujii Masao)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix parsing of WAL file names in <application>pg_receivexlog</application>
      (Heikki Linnakangas)
     </para>

     <para>
      This error made <application>pg_receivexlog</application> unable to restart
      streaming after stopping, once at least 4 GB of WAL had been written.
     </para>
    </listitem>

    <listitem>
     <para>
      Report out-of-disk-space failures properly
      in <application>pg_upgrade</application> (Peter Eisentraut)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <application>ecpg</application> search for quoted cursor names
      case-sensitively (Zolt&aacute;n B&ouml;sz&ouml;rm&eacute;nyi)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix <application>ecpg</application>'s processing of lists of variables
      declared <type>varchar</type> (Zolt&aacute;n B&ouml;sz&ouml;rm&eacute;nyi)
     </para>
    </listitem>

    <listitem>
     <para>
      Make <filename>contrib/lo</filename> defend against incorrect trigger definitions
      (Marc Cousin)
     </para>
    </listitem>

    <listitem>
     <para>
      Update time zone data files to <application>tzdata</application> release 2013h
      for DST law changes in Argentina, Brazil, Jordan, Libya,
      Liechtenstein, Morocco, and Palestine.  Also, new timezone
      abbreviations WIB, WIT, WITA for Indonesia.
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3-1">
  <title>Release 9.3.1</title>

  <formalpara>
  <title>Release date:</title>
  <para>2013-10-10</para>
  </formalpara>

  <para>
   This release contains a variety of fixes from 9.3.0.
   For information about new features in the 9.3 major release, see
   <xref linkend="release-9-3"/>.
  </para>

  <sect2>
   <title>Migration to Version 9.3.1</title>

   <para>
    A dump/restore is not required for those running 9.3.X.
   </para>

   <para>
    However, if you use the <literal>hstore</literal> extension, see the
    first changelog entry.
   </para>

  </sect2>

  <sect2>
   <title>Changes</title>

   <itemizedlist>

    <listitem>
     <para>
      Ensure new-in-9.3 JSON functionality is added to the <literal>hstore</literal>
      extension during an update (Andrew Dunstan)
     </para>

     <para>
      Users who upgraded a pre-9.3 database containing <literal>hstore</literal>
      should execute
<programlisting>
ALTER EXTENSION hstore UPDATE;
</programlisting>
      after installing 9.3.1, to add two new JSON functions and a cast.
      (If <literal>hstore</literal> is already up to date, this command does
      nothing.)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix memory leak when creating B-tree indexes on range columns
      (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix memory leak caused by <function>lo_open()</function> failure
      (Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Serializable snapshot fixes (Kevin Grittner, Heikki Linnakangas)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix deadlock bug in libpq when using SSL (Stephen Frost)
     </para>
    </listitem>

    <listitem>
     <para>
      Fix timeline handling bugs in <application>pg_receivexlog</application>
      (Heikki Linnakangas, Andrew Gierth)
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent <command>CREATE FUNCTION</command> from checking <command>SET</command>
      variables unless function body checking is enabled (Tom Lane)
     </para>
    </listitem>

    <listitem>
     <para>
      Remove rare inaccurate warning during vacuum of index-less tables
      (Heikki Linnakangas)
     </para>
    </listitem>

   </itemizedlist>

  </sect2>
 </sect1>

 <sect1 id="release-9-3">
  <title>Release 9.3</title>

  <formalpara>
   <title>Release date:</title>
   <para>2013-09-09</para>
  </formalpara>

  <sect2>
   <title>Overview</title>

   <para>
    Major enhancements in <productname>PostgreSQL</productname> 9.3 include:
   </para>

   <!-- This list duplicates items below, but without authors or details-->

   <itemizedlist>

    <listitem>
     <para>
      Add <link linkend="sql-creatematerializedview">materialized
      views</link>
     </para>
    </listitem>

    <listitem>
     <para>
      Make simple views <link
      linkend="sql-createview-updatable-views">auto-updatable</link>
     </para>
    </listitem>

    <listitem>
     <para>
      Add many features for the <type>JSON</type> data type,
      including <link linkend="functions-json">operators and functions</link>
      to extract elements from <type>JSON</type> values
     </para>
    </listitem>

    <listitem>
     <para>
      Implement <acronym>SQL</acronym>-standard <link
      linkend="queries-lateral"><literal>LATERAL</literal></link> option for
      <literal>FROM</literal>-clause subqueries and function calls
     </para>
    </listitem>

    <listitem>
     <para>
      Allow <link linkend="sql-createforeigndatawrapper">foreign data
      wrappers</link> to support writes (inserts/updates/deletes) on foreign
      tables
     </para>
    </listitem>

    <listitem>
     <para>
      Add a <link linkend="postgres-fdw"><productname>Postgres</productname> foreign
      data wrapper</link> to allow access to
      other <productname>Postgres</productname> servers
     </para>
    </listitem>

    <listitem>
     <para>
      Add support for <link linkend="event-triggers">event triggers</link>
     </para>
    </listitem>

    <listitem>
     <para>
      Add optional ability to <link
      linkend="app-initdb-data-checksums">checksum</link> data pages and
      report corruption
     </para>
    </listitem>

    <listitem>
     <para>
      Prevent non-key-field row updates from blocking foreign key checks
     </para>
    </listitem>

    <listitem>
     <para>
      Greatly reduce System V <link linkend="sysvipc">shared
      memory</link> requirements
     </para>
    </listitem>

   </itemizedlist>

   <para>
    The above items are explained in more detail in the sections below.
   </para>

  </sect2>

  <sect2>

  <title>Migration to Version 9.3</title>

   <para>
    A dump/restore using <link
    linkend="app-pg-dumpall"><application>pg_dumpall</application></link>, or use
    of <link linkend="pgupgrade"><application>pg_upgrade</application></link>, is
    required for those wishing to migrate data from any previous release.
   </para>

   <para>
    Version 9.3 contains a number of changes that may affect compatibility
    with previous releases.  Observe the following incompatibilities:
   </para>

   <sect3>
    <title>Server Settings</title>

     <itemizedlist>

      <listitem>
       <para>
        Rename <varname>replication_timeout</varname> to <link
        linkend="guc-wal-sender-timeout"><varname>wal_sender_timeout</varname></link>
        (Amit Kapila)
       </para>

       <para>
        This setting controls the <link
        linkend="wal"><acronym>WAL</acronym></link> sender timeout.
       </para>
      </listitem>

      <listitem>
       <para>
        Require superuser privileges to set <link
        linkend="guc-commit-delay"><varname>commit_delay</varname></link>
        because it can now potentially delay other sessions (Simon Riggs)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow in-memory sorts to use their full memory allocation (Jeff Janes)
       </para>

       <para>
        Users who have set <link
        linkend="guc-work-mem"><varname>work_mem</varname></link> based on the
        previous behavior may need to revisit that setting.
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

   <sect3>
    <title>Other</title>

     <itemizedlist>

      <listitem>
       <para>
        Throw an error if a tuple to be updated or deleted has already been
        updated or deleted by a <literal>BEFORE</literal> trigger (Kevin Grittner)
       </para>

       <para>
        Formerly, the originally-intended update was silently skipped,
        resulting in logical inconsistency since the trigger might have
        propagated data to other places based on the intended update.
        Now an error is thrown to prevent the inconsistent results from being
        committed.  If this change affects your application, the best solution
        is usually to move the data-propagation actions to
        an <literal>AFTER</literal> trigger.
       </para>

       <para>
        This error will also be thrown if a query invokes a volatile function
        that modifies rows that are later modified by the query itself.
        Such cases likewise previously resulted in silently skipping updates.
       </para>
      </listitem>

      <listitem>
       <para>
        Change multicolumn <link linkend="sql-createtable"><literal>ON UPDATE
        SET NULL/SET DEFAULT</literal></link> foreign key actions to affect
        all columns of the constraint, not just those changed in the
        <command>UPDATE</command> (Tom Lane)
       </para>

       <para>
        Previously, we would set only those referencing columns that
        correspond to referenced columns that were changed by
        the <command>UPDATE</command>.  This was what was required by SQL-92,
        but more recent editions of the SQL standard specify the new behavior.
       </para>
      </listitem>

      <listitem>
       <para>
        Force cached plans to be replanned if the <link
        linkend="guc-search-path"><varname>search_path</varname></link> changes
        (Tom Lane)
       </para>

       <para>
        Previously, cached plans already generated in the current session were
        not redone if the query was re-executed with a
        new <varname>search_path</varname> setting, resulting in surprising behavior.
       </para>
      </listitem>

      <listitem>
       <para>
        Fix <link
        linkend="functions-formatting-table"><function>to_number()</function></link>
        to properly handle a period used as a thousands separator (Tom Lane)
       </para>

       <para>
        Previously, a period was considered to be a decimal point even when
        the locale says it isn't and the <literal>D</literal> format code is used to
        specify use of the locale-specific decimal point.  This resulted in
        wrong answers if <literal>FM</literal> format was also used.
       </para>
      </listitem>

      <listitem>
       <para>
        Fix <literal>STRICT</literal> non-set-returning functions that have
        set-returning functions in their arguments to properly return null
        rows (Tom Lane)
       </para>

       <para>
        A null value passed to the strict function should result in a null
        output, but instead, that output row was suppressed entirely.
       </para>
      </listitem>

      <listitem>
       <para>
        Store <link linkend="wal"><acronym>WAL</acronym></link> in a continuous
        stream, rather than skipping the last 16MB segment every 4GB
        (Heikki Linnakangas)
       </para>

       <para>
        Previously, <acronym>WAL</acronym> files with names ending in <literal>FF</literal>
        were not used because of this skipping.  If you have <acronym>WAL</acronym>
        backup or restore scripts that took this behavior into account, they
        will need to be adjusted.
       </para>
      </listitem>

      <listitem>
       <para>
        In <link
        linkend="catalog-pg-constraint"><structname>pg_constraint.confmatchtype</structname></link>,
        store the default foreign key match type (non-<literal>FULL</literal>,
        non-<literal>PARTIAL</literal>) as <literal>s</literal> for <quote>simple</quote>
        (Tom Lane)
       </para>

       <para>
        Previously this case was represented by <literal>u</literal>
        for <quote>unspecified</quote>.
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

  </sect2>

  <sect2>
   <title>Changes</title>

   <para>
    Below you will find a detailed account of the changes between
    <productname>PostgreSQL</productname> 9.3 and the previous major
    release.
   </para>

   <sect3>
    <title>Server</title>

    <sect4>
     <title>Locking</title>

     <itemizedlist>

      <listitem>
       <para>
        Prevent non-key-field row updates from blocking foreign key checks
        (&Aacute;lvaro Herrera, Noah Misch, Andres Freund, Alexander
        Shulgin, Marti Raudsepp, Alexander Shulgin)
       </para>

       <para>
        This change improves concurrency and reduces the probability of
        deadlocks when updating tables involved in a foreign-key constraint.
        <command>UPDATE</command>s that do not change any columns referenced in a
        foreign key now take the new <literal>NO KEY UPDATE</literal> lock mode on
        the row, while foreign key checks use the new <literal>KEY SHARE</literal>
        lock mode, which does not conflict with <literal>NO KEY UPDATE</literal>.
        So there is no blocking unless a foreign-key column is changed.
       </para>
      </listitem>

      <listitem>
       <para>
        Add configuration variable <link
        linkend="guc-lock-timeout"><varname>lock_timeout</varname></link> to
        allow limiting how long a session will wait to acquire any one lock
        (Zolt&aacute;n B&ouml;sz&ouml;rm&eacute;nyi)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title>Indexes</title>

     <itemizedlist>

      <listitem>
       <para>
        Add <link linkend="rangetypes-indexing"><acronym>SP-GiST</acronym></link>
        support for range data types (Alexander Korotkov)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link linkend="gist"><acronym>GiST</acronym></link> indexes to be
        unlogged (Jeevan Chalke)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve performance of <acronym>GiST</acronym> index insertion by randomizing
        the choice of which page to descend to when there are multiple equally
        good alternatives (Heikki Linnakangas)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve concurrency of hash index operations (Robert Haas)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title>Optimizer</title>

     <itemizedlist>

      <listitem>
       <para>
        Collect and use histograms of upper and lower bounds, as well as range
        lengths, for <link linkend="rangetypes">range types</link>
        (Alexander Korotkov)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve optimizer's cost estimation for index access (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve optimizer's hash table size estimate for
        doing <literal>DISTINCT</literal> via hash aggregation (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Suppress no-op Result and Limit plan nodes
        (Kyotaro Horiguchi, Amit Kapila, Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Reduce optimizer overhead by not keeping plans on the basis of cheap
        startup cost when the optimizer only cares about total cost overall
        (Tom Lane)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title>General Performance</title>

     <itemizedlist>

      <listitem>
       <para>
        Add <link linkend="sql-copy"><command>COPY FREEZE</command></link>
        option to avoid the overhead of marking tuples as frozen later
        (Simon Riggs, Jeff Davis)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve performance of <link
        linkend="datatype-numeric"><type>NUMERIC</type></link> calculations
        (Kyotaro Horiguchi)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve synchronization of sessions waiting for <link
        linkend="guc-commit-delay"><varname>commit_delay</varname></link>
        (Peter Geoghegan)
       </para>

       <para>
        This greatly improves the usefulness of <varname>commit_delay</varname>.
       </para>
      </listitem>

      <listitem>
       <para>
        Improve performance of the <link
        linkend="sql-createtable"><command>CREATE TEMPORARY TABLE ... ON
        COMMIT DELETE ROWS</command></link> option by not truncating such temporary
        tables in transactions that haven't touched any temporary tables
        (Heikki Linnakangas)
       </para>
      </listitem>

      <listitem>
       <para>
        Make vacuum recheck visibility after it has removed expired tuples
        (Pavan Deolasee)
       </para>

       <para>
        This increases the chance of a page being marked as all-visible.
       </para>
      </listitem>

      <listitem>
       <para>
        Add per-resource-owner lock caches (Jeff Janes)
       </para>

       <para>
        This speeds up lock bookkeeping at statement completion in
        multi-statement transactions that hold many locks; it is particularly
        useful for <application>pg_dump</application>.
       </para>
      </listitem>

      <listitem>
       <para>
        Avoid scanning the entire relation cache at commit of a transaction
        that creates a new relation (Jeff Janes)
       </para>

       <para>
        This speeds up sessions that create many tables in successive
        small transactions, such as a <application>pg_restore</application> run.
       </para>
      </listitem>

      <listitem>
       <para>
        Improve performance of transactions that drop many relations
        (Tomas Vondra)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title>Monitoring</title>

     <itemizedlist>

      <listitem>
       <para>
        Add optional ability to <link
        linkend="app-initdb-data-checksums">checksum</link> data pages and
        report corruption (Simon Riggs, Jeff Davis, Greg Smith, Ants Aasma)
       </para>

       <para>
        The checksum option can be set during <link
        linkend="app-initdb">initdb</link>.
       </para>
      </listitem>

      <listitem>
       <para>
        Split the <link linkend="monitoring-stats">statistics collector's</link>
        data file into separate global and per-database files (Tomas Vondra)
       </para>

       <para>
        This reduces the I/O required for statistics tracking.
       </para>
      </listitem>

      <listitem>
       <para>
        Fix the statistics collector to operate properly in cases where the
        system clock goes backwards (Tom Lane)
       </para>

       <para>
        Previously, statistics collection would stop until the time again
        reached the latest time previously recorded.
       </para>
      </listitem>

      <listitem>
       <para>
        Emit an informative message to postmaster standard error when we
        are about to stop logging there
        (Tom Lane)
       </para>

       <para>
        This should help reduce user confusion about where to look for log
        output in common configurations that log to standard error only during
        postmaster startup.
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title>Authentication</title>

     <itemizedlist>

      <listitem>
       <para>
        When an authentication failure occurs, log the relevant
        <link linkend="auth-pg-hba-conf"><filename>pg_hba.conf</filename></link>
        line, to ease debugging of unintended failures
        (Magnus Hagander)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <link linkend="auth-ldap"><acronym>LDAP</acronym></link> error
        reporting and documentation (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Add support for specifying <acronym>LDAP</acronym> authentication parameters
        in <acronym>URL</acronym> format, per RFC 4516 (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Change the <link
        linkend="guc-ssl-ciphers"><varname>ssl_ciphers</varname></link> parameter
        to start with <literal>DEFAULT</literal>, rather than <literal>ALL</literal>,
        then remove insecure ciphers (Magnus Hagander)
       </para>

       <para>
        This should yield a more appropriate SSL cipher set.
       </para>
      </listitem>

      <listitem>
       <para>
        Parse and load <link
        linkend="auth-username-maps"><filename>pg_ident.conf</filename></link>
        once, not during each connection (Amit Kapila)
       </para>

       <para>
        This is similar to how <filename>pg_hba.conf</filename> is processed.
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title>Server Settings</title>

     <itemizedlist>

      <listitem>
       <para>
        Greatly reduce System V <link linkend="sysvipc">shared
        memory</link> requirements (Robert Haas)
       </para>

       <para>
        On Unix-like systems, <function>mmap()</function> is now used for most
        of <productname>PostgreSQL</productname>'s shared memory.  For most users, this
        will eliminate any need to adjust kernel parameters for shared memory.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow the postmaster to listen on multiple Unix-domain sockets
        (Honza Hor&aacute;k)
       </para>

       <para>
        The configuration parameter
        <varname>unix_socket_directory</varname> is replaced by <link
        linkend="guc-unix-socket-directories"><varname>unix_socket_directories</varname></link>,
        which accepts a list of directories.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow a directory of configuration files to be processed (Magnus
        Hagander, Greg Smith, Selena Deckelmann)
       </para>

       <para>
        Such a directory is specified with <link
        linkend="config-includes"><varname>include_dir</varname></link> in the server
        configuration file.
       </para>
      </listitem>

      <listitem>
       <para>
        Increase the maximum <link
        linkend="app-initdb">initdb</link>-configured value for <link
        linkend="guc-shared-buffers"><varname>shared_buffers</varname></link>
        to 128MB (Robert Haas)
       </para>

       <para>
        This is the maximum value that initdb will attempt to set in <link
        linkend="config-setting-configuration-file"><filename>postgresql.conf</filename></link>;
        the previous maximum was 32MB.
       </para>
      </listitem>

      <listitem>
       <para>
        Remove the <link linkend="guc-external-pid-file">external
        <acronym>PID</acronym> file</link>, if any, on postmaster exit
        (Peter Eisentraut)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3>
    <title>Replication and Recovery</title>

     <itemizedlist>

      <listitem>
       <para>
        Allow a streaming replication standby to <link
        linkend="protocol-replication">follow a timeline switch</link>
        (Heikki Linnakangas)
       </para>

       <para>
        This allows streaming standby servers to receive WAL data from a slave
        newly promoted to master status.  Previously, other standbys would
        require a resync to begin following the new master.
       </para>
      </listitem>

      <listitem>
       <para>
        Add <acronym>SQL</acronym> functions <link
        linkend="functions-admin-backup"><function>pg_is_in_backup()</function></link>
        and <link
        linkend="functions-admin-backup"><function>pg_backup_start_time()</function></link>
        (Gilles Darold)
       </para>

       <para>
        These functions report the status of base backups.
       </para>
      </listitem>

      <listitem>
       <para>
        Improve performance of streaming log shipping with <link
        linkend="guc-synchronous-commit"><varname>synchronous_commit</varname></link>
        disabled (Andres Freund)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow much faster promotion of a streaming standby to primary (Simon
        Riggs, Kyotaro Horiguchi)
       </para>
      </listitem>

      <listitem>
       <para>
        Add the last checkpoint's redo location to <link
        linkend="app-pgcontroldata"><application>pg_controldata</application></link>'s
        output (Fujii Masao)
       </para>

       <para>
        This information is useful for determining which <acronym>WAL</acronym>
        files are needed for restore.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow tools like <link
        linkend="app-pgreceivewal"><application>pg_receivexlog</application></link>
        to run on computers with different architectures (Heikki
        Linnakangas)
       </para>

       <para>
        WAL files can still only be replayed on servers with the same
        architecture as the primary; but they can now be transmitted to and
        stored on machines of any architecture, since the
        streaming replication protocol is now machine-independent.
       </para>
      </listitem>

      <listitem>
       <para>
        Make <link
        linkend="app-pgbasebackup"><application>pg_basebackup</application></link>
        <option>--write-recovery-conf</option> output a
        minimal <filename>recovery.conf</filename> file (Zolt&aacute;n
        B&ouml;sz&ouml;rm&eacute;nyi, Magnus Hagander)
       </para>

       <para>
        This simplifies setting up a standby server.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link
        linkend="app-pgreceivewal"><application>pg_receivexlog</application></link>
        and <link
        linkend="app-pgbasebackup"><application>pg_basebackup</application></link>
        <option>--xlog-method</option> to handle streaming timeline switches
        (Heikki Linnakangas)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link
        linkend="guc-wal-receiver-timeout"><varname>wal_receiver_timeout</varname></link>
        parameter to control the <acronym>WAL</acronym> receiver's timeout
        (Amit Kapila)
       </para>

       <para>
        This allows more rapid detection of connection failure.
       </para>
      </listitem>

      <listitem>
       <para>
        Change the <link linkend="wal"><acronym>WAL</acronym></link> record format to
        allow splitting the record header across pages (Heikki Linnakangas)
       </para>

       <para>
        The new format is slightly more compact, and is more efficient to
        write.
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

   <sect3>
    <title>Queries</title>

     <itemizedlist>

      <listitem>
       <para>
        Implement <acronym>SQL</acronym>-standard <link
        linkend="queries-lateral"><literal>LATERAL</literal></link> option for
        <literal>FROM</literal>-clause subqueries and function calls (Tom Lane)
       </para>

       <para>
        This feature allows subqueries and functions in <literal>FROM</literal> to
        reference columns from other tables in the <literal>FROM</literal>
        clause. The <literal>LATERAL</literal> keyword is optional for functions.
       </para>
      </listitem>

      <listitem>
       <para>
        Add support for piping <link
        linkend="sql-copy"><command>COPY</command></link> and <link
        linkend="app-psql"><application>psql</application></link> <command>\copy</command>
        data to/from an external program (Etsuro Fujita)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow a multirow <link
        linkend="sql-values"><literal>VALUES</literal></link> clause in a rule
        to reference <literal>OLD</literal>/<literal>NEW</literal> (Tom Lane)
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

   <sect3>
    <title>Object Manipulation</title>

     <itemizedlist>

      <listitem>
       <para>
        Add support for <link linkend="event-triggers">event triggers</link>
        (Dimitri Fontaine, Robert Haas, &Aacute;lvaro Herrera)
       </para>

       <para>
        This allows server-side functions written in event-enabled
        languages to be called when DDL commands are run.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link linkend="sql-createforeigndatawrapper">foreign data
        wrappers</link> to support writes (inserts/updates/deletes) on foreign
        tables (KaiGai Kohei)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link linkend="sql-createschema"><command>CREATE SCHEMA ... IF
        NOT EXISTS</command></link> clause (Fabr&iacute;zio de Royes Mello)
       </para>
      </listitem>

      <listitem>
       <para>
        Make <link linkend="sql-reassign-owned"><command>REASSIGN
        OWNED</command></link> also change ownership of shared objects
        (&Aacute;lvaro Herrera)
       </para>
      </listitem>

      <listitem>
       <para>
        Make <link linkend="sql-createaggregate"><command>CREATE
        AGGREGATE</command></link> complain if the given initial value string is not
        valid input for the transition datatype (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Suppress <link linkend="sql-createtable"><command>CREATE
        TABLE</command></link>'s messages about implicit index and sequence creation
        (Robert Haas)
       </para>

       <para>
        These messages now appear at <literal>DEBUG1</literal> verbosity, so that
        they will not be shown by default.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link linkend="sql-droptable"><command>DROP TABLE IF
        EXISTS</command></link> to succeed when a non-existent schema is specified
        in the table name (Bruce Momjian)
       </para>

       <para>
         Previously, it threw an error if the schema did not exist.
       </para>
      </listitem>

      <listitem>
       <para>
        Provide clients with <link
        linkend="libpq-pqresulterrorfield">constraint violation details</link>
        as separate fields (Pavel Stehule)
       </para>

       <para>
        This allows clients to retrieve table, column, data type, or
        constraint name error details.  Previously such information had to be
        extracted from error strings.  Client library support is required to
        access these fields.
       </para>
      </listitem>

     </itemizedlist>

    <sect4>
     <title><command>ALTER</command></title>

     <itemizedlist>

      <listitem>
       <para>
        Support <literal>IF NOT EXISTS</literal> option in <link
        linkend="sql-altertype"><command>ALTER TYPE ... ADD VALUE</command></link>
        (Andrew Dunstan)
       </para>

       <para>
        This is useful for conditionally adding values to enumerated types.
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link linkend="sql-alterrole"><command>ALTER ROLE ALL
        SET</command></link> to establish settings for all users (Peter Eisentraut)
       </para>

       <para>
        This allows settings to apply to all users in all databases. <link
        linkend="sql-alterdatabase"><command>ALTER DATABASE SET</command></link>
        already allowed addition of settings for all users in a single
        database.  <filename>postgresql.conf</filename> has a similar effect.
       </para>
      </listitem>

      <listitem>
       <para>
        Add support for <link linkend="sql-alterrule"><command>ALTER RULE
        ... RENAME</command></link> (Ali Dar)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title><link linkend="rules-views"><command>VIEWs</command></link></title>

     <itemizedlist>

      <listitem>
       <para>
        Add <link linkend="sql-creatematerializedview">materialized
        views</link> (Kevin Grittner)
       </para>

       <para>
        Unlike ordinary views, where the base tables are read on every access,
        materialized views create physical tables at creation or refresh time.
        Access to the materialized view then reads from its physical
        table. There is not yet any facility for incrementally refreshing
        materialized views or auto-accessing them via base table access.
       </para>
      </listitem>

      <listitem>
       <para>
        Make simple views <link
        linkend="sql-createview-updatable-views">auto-updatable</link>
        (Dean Rasheed)
       </para>

       <para>
        Simple views that reference some or all columns from a
        single base table are now updatable by default. More
        complex views can be made updatable using <link
        linkend="sql-createtrigger"><literal>INSTEAD OF</literal></link> triggers
        or <link linkend="sql-createrule"><literal>INSTEAD</literal></link> rules.
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link linkend="sql-createview"><command>CREATE RECURSIVE
        VIEW</command></link> syntax (Peter Eisentraut)
       </para>

       <para>
        Internally this is translated into <command>CREATE VIEW ... WITH
        RECURSIVE ...</command>.
       </para>
      </listitem>

      <listitem>
       <para>
        Improve view/rule printing code to handle cases where referenced
        tables are renamed, or columns are renamed, added, or dropped
        (Tom Lane)
       </para>

       <para>
        Table and column renamings can produce cases where, if we merely
        substitute the new name into the original text of a rule or view, the
        result is ambiguous.  This change fixes the rule-dumping code to insert
        manufactured table and column aliases when needed to preserve the
        original semantics.
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3>
    <title>Data Types</title>

    <itemizedlist>

      <listitem>
       <para>
        Increase the maximum size of <link linkend="largeobjects">large
        objects</link> from 2GB to 4TB (Nozomi Anzai, Yugo Nagata)
       </para>

       <para>
        This change includes adding 64-bit-capable large object access
        functions, both in the server and in libpq.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow text <link linkend="datatype-timezones">timezone
        designations</link>, e.g. <quote>America/Chicago</quote>, in the
        <quote>T</quote> field of <acronym>ISO</acronym>-format <type>timestamptz</type>
        input (Bruce Momjian)
       </para>
      </listitem>

    </itemizedlist>

   <sect4>
    <title><link linkend="datatype-json"><type>JSON</type></link></title>

    <itemizedlist>

      <listitem>
       <para>
        Add <link linkend="functions-json">operators and functions</link>
        to extract elements from <type>JSON</type> values (Andrew Dunstan)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <type>JSON</type> values to be <link
        linkend="functions-json">converted into records</link>
        (Andrew Dunstan)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link linkend="functions-json">functions</link> to convert
        scalars, records, and <type>hstore</type> values to <type>JSON</type> (Andrew
        Dunstan)
       </para>
      </listitem>

    </itemizedlist>

   </sect4>

   </sect3>


   <sect3>
    <title>Functions</title>

     <itemizedlist>

      <listitem>
       <para>
        Add <link
        linkend="array-functions-table"><function>array_remove()</function></link>
        and <link
        linkend="array-functions-table"><function>array_replace()</function></link>
        functions (Marco Nenciarini, Gabriele Bartolini)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link
        linkend="functions-string-other"><function>concat()</function></link>
        and <link
        linkend="functions-string-format"><function>format()</function></link>
        to properly expand <literal>VARIADIC</literal>-labeled arguments
        (Pavel Stehule)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <link
        linkend="functions-string-format"><function>format()</function></link>
        to provide field width and left/right alignment options (Pavel Stehule)
       </para>
      </listitem>

      <listitem>
       <para>
        Make <link
        linkend="functions-formatting-table"><function>to_char()</function></link>,
        <link
        linkend="functions-formatting-table"><function>to_date()</function></link>,
        and <link
        linkend="functions-formatting-table"><function>to_timestamp()</function></link>
        handle negative (BC) century values properly
        (Bruce Momjian)
       </para>

       <para>
        Previously the behavior was either wrong or inconsistent
        with positive/<acronym>AD</acronym> handling, e.g. with the format mask
        <quote>IYYY-IW-DY</quote>.
       </para>
      </listitem>

      <listitem>
       <para>
        Make <link
        linkend="functions-formatting-table"><function>to_date()</function></link>
        and <link
        linkend="functions-formatting-table"><function>to_timestamp()</function></link>
        return proper results when mixing <acronym>ISO</acronym> and Gregorian
        week/day designations (Bruce Momjian)
       </para>
      </listitem>

      <listitem>
       <para>
        Cause <link
        linkend="functions-info-catalog-table"><function>pg_get_viewdef()</function></link>
        to start a new line by default after each <literal>SELECT</literal> target
        list entry and <literal>FROM</literal> entry (Marko Tiikkaja)
       </para>

       <para>
        This reduces line length in view printing, for instance in <link
        linkend="app-pgdump"><application>pg_dump</application></link> output.
       </para>
      </listitem>

      <listitem>
       <para>
        Fix <function>map_sql_value_to_xml_value()</function> to print values of
        domain types the same way their base type would be printed
        (Pavel Stehule)
       </para>

       <para>
        There are special formatting rules for certain built-in types such as
        <type>boolean</type>; these rules now also apply to domains over these
        types.
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

   <sect3>
    <title>Server-Side Languages</title>

    <sect4>
     <title><link linkend="plpgsql">PL/pgSQL</link> Server-Side Language</title>

     <itemizedlist>

      <listitem>
       <para>
        Allow PL/pgSQL to use <literal>RETURN</literal> with a composite-type
        expression (Asif Rehman)
       </para>

       <para>
        Previously, in a function returning a composite type,
        <literal>RETURN</literal> could only reference a variable of that type.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow PL/pgSQL to access <link
        linkend="plpgsql-exception-diagnostics">constraint violation
        details</link> as separate fields (Pavel Stehule)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow PL/pgSQL to access the number of rows processed by
        <link linkend="sql-copy"><command>COPY</command></link> (Pavel Stehule)
       </para>

       <para>
        A <command>COPY</command> executed in a PL/pgSQL function now updates the
        value retrieved by <link
        linkend="plpgsql-statements-diagnostics"><command>GET DIAGNOSTICS
        x = ROW_COUNT</command></link>.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow unreserved keywords to be used as identifiers everywhere in
        PL/pgSQL (Tom Lane)
       </para>

       <para>
        In certain places in the PL/pgSQL grammar, keywords had to be quoted
        to be used as identifiers, even if they were nominally unreserved.
       </para>
      </listitem>

    </itemizedlist>

    </sect4>

    <sect4>
     <title><link linkend="plpython">PL/Python</link> Server-Side Language</title>

     <itemizedlist>

      <listitem>
       <para>
        Add PL/Python result object string handler (Peter Eisentraut)
       </para>

       <para>
        This allows <literal>plpy.debug(rv)</literal> to output something reasonable.
       </para>
      </listitem>

      <listitem>
       <para>
        Make PL/Python convert OID values to a proper Python numeric type
        (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Handle <link linkend="spi"><acronym>SPI</acronym></link> errors raised
        explicitly (with PL/Python's <literal>RAISE</literal>) the same as
        internal <acronym>SPI</acronym> errors (Oskari Saarenmaa and Jan Urbanski)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3>
    <title>Server Programming Interface (<link linkend="spi">SPI</link>)</title>

     <itemizedlist>

      <listitem>
       <para>
        Prevent leakage of <acronym>SPI</acronym> tuple tables during subtransaction
        abort (Tom Lane)
       </para>

       <para>
        At the end of any failed subtransaction, the core SPI code now
        releases any SPI tuple tables that were created during that
        subtransaction.  This avoids the need for SPI-using code to keep track
        of such tuple tables and release them manually in error-recovery code.
        Failure to do so caused a number of transaction-lifespan memory leakage
        issues in PL/pgSQL and perhaps other SPI clients.  <link
        linkend="spi-spi-freetupletable"><function>SPI_freetuptable()</function></link>
        now protects itself against multiple freeing requests, so any existing
        code that did take care to clean up shouldn't be broken by this change.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <acronym>SPI</acronym> functions to access the number of rows processed
        by <link linkend="sql-copy"><command>COPY</command></link> (Pavel Stehule)
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

   <sect3>
    <title>Client Applications</title>

    <itemizedlist>

      <listitem>
       <para>
        Add command-line utility <link
        linkend="app-pg-isready"><application>pg_isready</application></link> to
        check if the server is ready to accept connections (Phil Sorber)
       </para>
      </listitem>

      <listitem>
       <para>
        Support multiple <option>--table</option> arguments for <link
        linkend="app-pgrestore"><application>pg_restore</application></link>,
        <link linkend="app-clusterdb"><application>clusterdb</application></link>,
        <link linkend="app-reindexdb"><application>reindexdb</application></link>,
        and <link linkend="app-vacuumdb"><application>vacuumdb</application></link>
        (Josh Kupershmidt)
       </para>

       <para>
        This is similar to the way <link
        linkend="app-pgdump"><application>pg_dump</application></link>'s
        <option>--table</option> option works.
       </para>
      </listitem>

      <listitem>
       <para>
        Add <option>--dbname</option> option to <link
        linkend="app-pg-dumpall"><application>pg_dumpall</application></link>, <link
        linkend="app-pgbasebackup"><application>pg_basebackup</application></link>, and
        <link
        linkend="app-pgreceivewal"><application>pg_receivexlog</application></link>
        to allow specifying a connection string (Amit Kapila)
       </para>
      </listitem>

      <listitem>
       <para>
        Add libpq function <link
        linkend="libpq-pqconninfo"><function>PQconninfo()</function></link>
        to return connection information (Zolt&aacute;n
        B&ouml;sz&ouml;rm&eacute;nyi, Magnus Hagander)
       </para>
      </listitem>

    </itemizedlist>

    <sect4>
     <title><link linkend="app-psql"><application>psql</application></link></title>

     <itemizedlist>

      <listitem>
       <para>
        Adjust function cost settings so <application>psql</application> tab
        completion and pattern searching are more efficient (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <application>psql</application>'s tab completion coverage (Jeff Janes,
        Dean Rasheed, Peter Eisentraut, Magnus Hagander)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow the <application>psql</application> <option>--single-transaction</option>
        mode to work when reading from standard input (Fabien Coelho,
        Robert Haas)
       </para>

       <para>
        Previously this option only worked when reading from a file.
       </para>
      </listitem>

      <listitem>
       <para>
        Remove <application>psql</application> warning when connecting to an older
        server (Peter Eisentraut)
       </para>

       <para>
        A warning is still issued when connecting to a server of a newer major
        version than <application>psql</application>'s.
       </para>
      </listitem>

     </itemizedlist>

    <sect5>
     <title><link linkend="app-psql-meta-commands">Backslash Commands</link></title>

     <itemizedlist>

      <listitem>
       <para>
        Add <application>psql</application> command <command>\watch</command> to repeatedly
        execute a SQL command (Will Leinweber)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <application>psql</application> command <command>\gset</command> to store query
        results in <application>psql</application> variables (Pavel Stehule)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <acronym>SSL</acronym> information to <application>psql</application>'s
        <command>\conninfo</command> command (Alastair Turner)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <quote>Security</quote> column to <application>psql</application>'s
        <command>\df+</command> output (Jon Erdman)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <application>psql</application> command <command>\l</command> to accept a database
        name pattern (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        In <application>psql</application>, do not allow <command>\connect</command> to
        use defaults if there is no active connection (Bruce Momjian)
       </para>

       <para>
        This might be the case if the server had crashed.
       </para>
      </listitem>

      <listitem>
       <para>
        Properly reset state after failure of a SQL command executed with
        <application>psql</application>'s <literal>\g</literal> <replaceable>file</replaceable>
        (Tom Lane)
       </para>

       <para>
        Previously, the output from subsequent SQL commands would unexpectedly
        continue to go to the same file.
       </para>
      </listitem>

     </itemizedlist>

    </sect5>

    <sect5>
     <title>Output</title>

     <itemizedlist>

      <listitem>
       <para>
        Add a <literal>latex-longtable</literal> output format to
        <application>psql</application> (Bruce Momjian)
       </para>

       <para>
        This format allows tables to span multiple pages.
       </para>
      </listitem>

      <listitem>
       <para>
        Add a <literal>border=3</literal> output mode to the <application>psql</application>
        <literal>latex</literal> format (Bruce Momjian)
       </para>
      </listitem>

      <listitem>
       <para>
        In <application>psql</application>'s tuples-only and expanded output modes, no
        longer emit <quote>(No rows)</quote> for zero rows (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        In <application>psql</application>'s unaligned, expanded output mode, no longer
        print an empty line for zero rows (Peter Eisentraut)
       </para>
      </listitem>

     </itemizedlist>

    </sect5>

    </sect4>

    <sect4>
     <title><link linkend="app-pgdump"><application>pg_dump</application></link></title>

     <itemizedlist>

      <listitem>
       <para>
        Add <application>pg_dump</application> <option>--jobs</option> option to dump tables in
        parallel (Joachim Wieland)
       </para>
      </listitem>

      <listitem>
       <para>
        Make <application>pg_dump</application> output functions in a more predictable
        order (Joel Jacobson)
       </para>
      </listitem>

      <listitem>
       <para>
        Fix tar files emitted by <application>pg_dump</application>
        to be <acronym>POSIX</acronym> conformant (Brian Weaver, Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <option>--dbname</option> option to <application>pg_dump</application>, for
        consistency with other client commands (Heikki Linnakangas)
       </para>

       <para>
        The database name could already be supplied last without a flag.
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title><link linkend="app-initdb"><application>initdb</application></link></title>

     <itemizedlist>

      <listitem>
       <para>
        Make initdb fsync the newly created data directory (Jeff Davis)
       </para>

       <para>
        This insures data integrity in event of a system crash shortly after
        initdb.  This can be disabled by using <option>--nosync</option>.
       </para>
      </listitem>

      <listitem>
       <para>
        Add initdb <option>--sync-only</option> option to sync the data directory to durable
        storage (Bruce Momjian)
       </para>

       <para>
        This is used by <link
        linkend="pgupgrade"><application>pg_upgrade</application></link>.
       </para>
      </listitem>

      <listitem>
       <para>
        Make initdb issue a warning about placing the data directory at the
        top of a file system mount point (Bruce Momjian)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

   </sect3>

   <sect3>
    <title>Source Code</title>

     <itemizedlist>

      <listitem>
       <para>
        Add infrastructure to allow plug-in <link
        linkend="bgworker">background worker processes</link>
        (&Aacute;lvaro Herrera)
       </para>
      </listitem>

      <listitem>
       <para>
        Create a centralized timeout <acronym>API</acronym> (Zolt&aacute;n
        B&ouml;sz&ouml;rm&eacute;nyi)
       </para>
      </listitem>

      <listitem>
       <para>
        Create libpgcommon and move <function>pg_malloc()</function> and other
        functions there (&Aacute;lvaro Herrera, Andres Freund)
       </para>

       <para>
        This allows libpgport to be used solely for portability-related code.
       </para>
      </listitem>

      <listitem>
       <para>
        Add support for list links embedded in larger structs (Andres Freund)
       </para>
      </listitem>

      <listitem>
       <para>
        Use <literal>SA_RESTART</literal> for all signals,
        including <literal>SIGALRM</literal> (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Ensure that the correct text domain is used when
        translating <function>errcontext()</function> messages
        (Heikki Linnakangas)
       </para>
      </listitem>

      <listitem>
       <para>
        Standardize naming of client-side memory allocation functions (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Provide support for <quote>static assertions</quote> that will fail at
        compile time if some compile-time-constant condition is not met
        (Andres Freund, Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Support <function>Assert()</function> in client-side code (Andrew Dunstan)
       </para>
      </listitem>

      <listitem>
       <para>
        Add decoration to inform the C compiler that some <function>ereport()</function>
        and <function>elog()</function> calls do not return (Peter Eisentraut,
        Andres Freund, Tom Lane, Heikki Linnakangas)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow options to be passed to the regression
        test output comparison utility via <link
        linkend="regress-evaluation"><envar>PG_REGRESS_DIFF_OPTS</envar></link>
        (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Add isolation tests for <link
        linkend="sql-createindex"><command>CREATE INDEX
        CONCURRENTLY</command></link> (Abhijit Menon-Sen)
       </para>
      </listitem>

      <listitem>
       <para>
        Remove typedefs for <type>int2</type>/<type>int4</type> as they are better
        represented as <type>int16</type>/<type>int32</type> (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Fix <link linkend="install">install-strip</link> on Mac <productname>OS
        X</productname> (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Remove <link linkend="configure">configure</link> flag
        <option>--disable-shared</option>, as it is no longer supported
        (Bruce Momjian)
       </para>
      </listitem>

      <listitem>
       <para>
        Rewrite pgindent in <application>Perl</application> (Andrew Dunstan)
       </para>
      </listitem>

      <listitem>
       <para>
        Provide Emacs macro to set Perl formatting to
        match <productname>PostgreSQL</productname>'s perltidy settings (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Run tool to check the keyword list whenever the backend grammar is
        changed (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Change the way <literal>UESCAPE</literal> is lexed, to significantly reduce
        the size of the lexer tables (Heikki Linnakangas)
       </para>
      </listitem>

      <listitem>
       <para>
        Centralize <application>flex</application> and <application>bison</application>
        <application>make</application> rules (Peter Eisentraut)
       </para>

       <para>
        This is useful for <application>pgxs</application> authors.
       </para>
      </listitem>

      <listitem>
       <para>
        Change many internal backend functions to return object <type>OID</type>s
        rather than void (Dimitri Fontaine)
       </para>

       <para>
        This is useful for event triggers.
       </para>
      </listitem>

      <listitem>
       <para>
        Invent pre-commit/pre-prepare/pre-subcommit events for transaction
        callbacks (Tom Lane)
       </para>

       <para>
        Loadable modules that use transaction callbacks might need modification
        to handle these new event types.
       </para>
      </listitem>

      <listitem>
       <para>
        Add function <link
        linkend="functions-info-catalog-table"><function>pg_identify_object()</function></link>
        to produce a machine-readable description of a database object
        (&Aacute;lvaro Herrera)
       </para>
      </listitem>

      <listitem>
       <para>
        Add post-<command>ALTER</command>-object server hooks (KaiGai Kohei)
       </para>
      </listitem>

      <listitem>
       <para>
        Implement a generic binary heap and use it for Merge-Append
        operations (Abhijit Menon-Sen)
       </para>
      </listitem>

      <listitem>
       <para>
        Provide a tool to help detect timezone abbreviation changes when
        updating the <filename>src/timezone/data</filename> files
        (Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <application>pkg-config</application> support for <application>libpq</application>
        and <application>ecpg</application> libraries (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Remove <filename>src/tools/backend</filename>, now that the content is on
        the <productname>PostgreSQL</productname> wiki (Bruce Momjian)
       </para>
      </listitem>

      <listitem>
       <para>
        Split out <link linkend="wal"><acronym>WAL</acronym></link> reading as
        an independent facility (Heikki Linnakangas, Andres Freund)
       </para>
      </listitem>

      <listitem>
       <para>
        Use a 64-bit integer to represent <link
        linkend="wal"><acronym>WAL</acronym></link> positions
        (<structname>XLogRecPtr</structname>) instead of two 32-bit integers
        (Heikki Linnakangas)
       </para>

       <para>
        Generally, tools that need to read the <acronym>WAL</acronym> format
        will need to be adjusted.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link linkend="plpython">PL/Python</link> to support
        platform-specific include directories (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <link linkend="plpython">PL/Python</link> on <productname>OS
        X</productname> to build against custom versions of <application>Python</application>
        (Peter Eisentraut)
       </para>
      </listitem>

     </itemizedlist>

   </sect3>

   <sect3>
    <title>Additional Modules</title>

    <itemizedlist>

      <listitem>
       <para>
        Add a <link linkend="postgres-fdw"><productname>Postgres</productname> foreign
        data wrapper</link> contrib module to allow access to
        other <productname>Postgres</productname> servers (Shigeru Hanada)
       </para>

       <para>
        This foreign data wrapper supports writes.
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link linkend="pgwaldump"><application>pg_xlogdump</application></link>
        contrib program (Andres Freund)
       </para>
      </listitem>

      <listitem>
       <para>
        Add support for indexing of regular-expression searches in
        <link linkend="pgtrgm"><productname>pg_trgm</productname></link>
        (Alexander Korotkov)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <link linkend="pgtrgm"><productname>pg_trgm</productname></link>'s
        handling of multibyte characters (Tom Lane)
       </para>

       <para>
        On a platform that does not have the wcstombs() or towlower() library
        functions, this could result in an incompatible change in the contents
        of <productname>pg_trgm</productname> indexes for non-ASCII data.  In such cases,
        <command>REINDEX</command> those indexes to ensure correct search results.
       </para>
      </listitem>

      <listitem>
       <para>
        Add a <link linkend="pgstattuple">pgstattuple</link> function to report
        the size of the pending-insertions list of a <acronym>GIN</acronym> index
        (Fujii Masao)
       </para>
      </listitem>

      <listitem>
       <para>
        Make <link linkend="oid2name"><application>oid2name</application></link>,
        <link linkend="pgbench"><application>pgbench</application></link>, and
        <link linkend="vacuumlo"><application>vacuumlo</application></link> set
        <varname>fallback_application_name</varname> (Amit Kapila)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve output of <link
        linkend="pgtesttiming"><application>pg_test_timing</application></link>
        (Bruce Momjian)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve output of <link
        linkend="pgtestfsync"><application>pg_test_fsync</application></link>
        (Peter Geoghegan)
       </para>
      </listitem>

      <listitem>
       <para>
        Create a dedicated foreign data wrapper, with its own option validator
        function, for <link linkend="dblink">dblink</link> (Shigeru Hanada)
       </para>

       <para>
        When using this FDW to define the target of a <application>dblink</application>
        connection, instead of using a hard-wired list of connection options,
        the underlying <application>libpq</application> library is consulted to see what
        connection options it supports.
       </para>
      </listitem>

    </itemizedlist>

    <sect4>
     <title><link linkend="pgupgrade"><application>pg_upgrade</application></link></title>

     <itemizedlist>

      <listitem>
       <para>
        Allow <application>pg_upgrade</application> to do dumps and restores in
        parallel (Bruce Momjian, Andrew Dunstan)
       </para>

       <para>
        This allows parallel schema dump/restore of databases, as well as
        parallel copy/link of data files per tablespace.  Use the
        <option>--jobs</option> option to specify the level of parallelism.
       </para>
      </listitem>

      <listitem>
       <para>
        Make <application>pg_upgrade</application> create Unix-domain sockets in
        the current directory (Bruce Momjian, Tom Lane)
       </para>

       <para>
        This reduces the possibility that someone will accidentally connect
        during the upgrade.
       </para>
      </listitem>

      <listitem>
       <para>
        Make <application>pg_upgrade</application> <option>--check</option> mode properly
        detect the location of non-default socket directories (Bruce
        Momjian, Tom Lane)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve performance of <application>pg_upgrade</application> for databases
        with many tables (Bruce Momjian)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <application>pg_upgrade</application>'s logs by showing
        executed commands (&Aacute;lvaro Herrera)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <application>pg_upgrade</application>'s status display during
        copy/link (Bruce Momjian)
       </para>
      </listitem>

     </itemizedlist>

    </sect4>

    <sect4>
     <title><link linkend="pgbench"><application>pgbench</application></link></title>

     <itemizedlist>

      <listitem>
       <para>
        Add <option>--foreign-keys</option> option to <application>pgbench</application>
        (Jeff Janes)
       </para>

       <para>
        This adds foreign key constraints to the standard tables created by
        <application>pgbench</application>, for use in foreign key performance testing.
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <application>pgbench</application> to aggregate performance statistics
        and produce output every <option>--aggregate-interval</option>
        seconds (Tomas Vondra)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <application>pgbench</application> <option>--sampling-rate</option> option
        to control the percentage of transactions logged (Tomas Vondra)
       </para>
      </listitem>

      <listitem>
       <para>
        Reduce and improve the status message output of
        <application>pgbench</application>'s initialization mode (Robert Haas,
        Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <application>pgbench</application> <option>-q</option> mode to print one output
        line every five seconds (Tomas Vondra)
       </para>
      </listitem>

      <listitem>
       <para>
        Output <application>pgbench</application> elapsed and estimated remaining
        time during initialization (Tomas Vondra)
       </para>
      </listitem>

      <listitem>
       <para>
        Allow <application>pgbench</application> to use much larger scale factors,
        by changing relevant columns from <type>integer</type> to <type>bigint</type>
        when the requested scale factor exceeds 20000
        (Greg Smith)
       </para>
      </listitem>

    </itemizedlist>

    </sect4>

   </sect3>

   <sect3>
    <title>Documentation</title>

    <itemizedlist>

      <listitem>
       <para>
        Allow <productname>EPUB</productname>-format documentation to be created
        (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Update <productname>FreeBSD</productname> kernel configuration documentation
        (Brad Davis)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <link linkend="tutorial-window"><literal>WINDOW</literal>
        function</link> documentation (Bruce Momjian, Florian Pflug)
       </para>
      </listitem>

      <listitem>
       <para>
        Add <link linkend="docguide-toolsets">instructions</link> for setting
        up the documentation tool chain on <productname>macOS</productname>
        (Peter Eisentraut)
       </para>
      </listitem>

      <listitem>
       <para>
        Improve <link
        linkend="guc-commit-delay"><varname>commit_delay</varname></link>
        documentation (Peter Geoghegan)
       </para>
      </listitem>

    </itemizedlist>

   </sect3>

  </sect2>
 </sect1>
