Fix markup by using <note> for comments.

HISTORY

@@ -7,56 +7,84 @@
                                       
    Major changes in this release:
    
-   Performance
-          IN/NOT IN subqueries are now much more efficient [1]
-          
-          Improved GROUP BY processing by using hash buckets [2]
-          
-          New multi-key hash join capability [3]
-          
-          ANSI joins are now better optimized [4]
-          
-          Faster and more powerful regular expression code [5]
-          
-          Function-inlining for simple SQL functions [6]
-          
-   IPv6
-          Full support for IPv6 connections and IPv6 address data types
-          [7]
-          
-   SSL
-          Major improvements in SSL performance and reliability [8]
-          
-   Index Growth Prevention
-          Allow free space map to efficiently reuse empty index pages,
-          and other free space management improvements. [9]
-          
-   Standards Compliance
-          Implement information schema
-          
-          Support for read-only transactions
-          
-          Make cursors comply more closely with the SQL standard
-          
-   New Client/Server Communication Protocol
-          New protocol improves connection speed/reliability, and adds
-          error codes, status information, a binary protocol, error
-          reporting verbosity, and cleaner startup packets.
-          
-   Holdable Cursors
-          Allow cursors to exist outside transactions
-          
-   Threads
-          libpq and ecpg are now fully thread-safe with
-          --enable-thread-safety [10]
-          
-   Contrib
-          New version of full text indexing (tsearch2)
-          
-          New autovacuum tool [11]
-          
-          Array handling has been improved and moved into the main server
-          [12]
+     * IN/NOT IN subqueries are now much more efficient
+       
+     Note: In previous releases, IN/NOT IN subqueries were joined to the
+     upper query by sequentially scanning the subquery looking for a
+     join. The 7.4 code uses the same sophisticated techniques used by
+     ordinary joins and so is much faster, and is now faster than EXISTS
+     subqueries.
+     * Improved GROUP BY processing by using hash buckets
+       
+     Note: In previous releases, GROUP BY totals were accumulated by
+     sequentially scanning the list of groups looking for a match; the
+     7.4 code places GROUP BY values in hash buckets so the proper match
+     can be found much quicker. This is particularly significant in
+     speeding up queries that have a large number of distinct GROUP BY
+     values.
+     * New multi-key hash join capability
+       
+     Note: In previous releases, hash joins could only occur on
+     single-column joins. This release allows multi-column hash joins.
+     * ANSI joins are now better optimized
+       
+     Note: Prior releases evaluated ANSI join syntax only in the order
+     specified by the query; 7.4 allows full optimization of queries
+     using ANSI join syntax, meaning the optimizer considers all
+     possible join orderings and chooses the most efficient.
+     * Faster and more powerful regular expression code
+       
+     Note: The entire regular expression module has been replaced with a
+     new version by Henry Spencer, originally written for TCL. The code
+     greatly improves performance and supports several flavors of
+     regular expressions.
+     * Function-inlining for simple SQL functions
+       
+     Note: Simple SQL functions can now be inlined by including their
+     SQL in the main query. This improves performance by preventing
+     repeated calls to the SQL function --- this allows simple SQL
+     functions to behave like macros.
+     * Full support for IPv6 connections and IPv6 address data types
+       
+     Note: Prior releases allowed only IPv6 connections and IP data
+     types only supported IPv4 addresses. This release adds full IPv6
+     support in both of these areas.
+     * Major improvements in SSL performance and reliability
+       
+     Note: Several people very familiar with the SSL API have overhauled
+     our SSL code to improve SSL key negotiation and error recovery.
+     * Allow free space map to efficiently reuse empty index pages, and
+       other free space management improvements.
+       
+     Note: In prior releases, index pages that were left empty because
+     of deleted rows could only be reused by rows with index values
+     similar to the original rows indexed on that page. In 7.4, VACUUM
+     records empty index pages and allows them to be used for any future
+     index rows.
+     * Implement information schema
+     * Support for read-only transactions
+     * Make cursors comply more closely with the SQL standard
+     * New protocol improves connection speed/reliability, and adds error
+       codes, status information, a binary protocol, error reporting
+       verbosity, and cleaner startup packets.
+     * Allow cursors to exist outside transactions, also called holdable
+       cursors
+     * libpq and ecpg are now fully thread-safe with
+       --enable-thread-safety
+       
+     Note: While prior libpq releases already supported threads, this
+     release improves thread safety by fixing some non-thread-safe code
+     that was used in the database connection routines.
+     * New version of full text indexing in /contrib/tsearch2
+     * New autovacuum tool in /contrib
+       
+     Note: This new tool monitors the database statistics tables for
+     INSERT/UPDATE/DELETE activity and automatically vacuums tables when
+     needed.
+     * Array handling has been improved and moved into the main server
+       
+     Note: Many array limitations have been removed and they behave more
+     like fully-supported data types.
      _________________________________________________________________
    
                           Migration to version 7.4
@@ -67,16 +95,27 @@
    Observe the following incompatibilities:
    
      * The server-side autocommit setting was removed and reimplemented
-       in client applications and languages. [13]
+       in client applications and languages.
+       
+     Note: Server-side autocommit was causing too many problems with
+     languages and applications that wanted to control their own
+     autocommit behavior so autocommit was removed from the server and
+     added to individual client API's as appropriate.
      * Error message wording has changed substantially in this release,
        and error codes have been added.
      * ANSI inner joins may behave differently because they are now
        better optimized
      * A number of server variables have been renamed for clarity,
        primarily those related to logging
-     * MOVE/FETCH 0 now does nothing [14]
+     * MOVE/FETCH 0 now does nothing
+       
+     Note: In prior releases, FETCH 0 would fetch all remaining rows,
+     and MOVE 0 would move to the end of the cursor.
      * MOVE/FETCH now returns the actual number of rows moved/fetched, or
-       zero if at the beginning/end of the cursor [15]
+       zero if at the beginning/end of the cursor
+       
+     Note: Prior releases would return the tuple count passed to the
+     command, not the actual number of rows FETCHed or MOVEd.
      * COPY now can process carriage-return and carriage-return/line-feed
        end-of-line terminated files.
      * Literal carriage-returns and line-feeds are no longer accepted as
@@ -85,37 +124,79 @@
        VARCHAR(n) / TEXT
      * FLOAT(p) now measures 'p' in bits, not digits
      * Ambiguous date values now must match the ordering specified by
-       DateStyle [16]
+       DateStyle
+       
+     Note: In prior releases, a date of 10/20/03 was interpreted as a
+     date in October even if the DateStyle specified the day should be
+     first. In 7.4, DateStyle is honored when converting such values and
+     will throw an error if the date is invalid for the current
+     DateStyle.
      * The oidrand(), oidsrand(), and userfntest() functions have been
-       removed. [17]
+       removed.
+       
+     Note: These functions were determined to be no longer useful.
      * 'now' will no longer work as a column default; now() or
-       CURRENT_TIMESTAMP should be used instead [18]
+       CURRENT_TIMESTAMP should be used instead
+       
+     Note: In prior releases, there was special code so the string 'now'
+     was interpreted at "INSERT" time and not at table creation time,
+     but this work around didn't cover all cases. Release 7.4 now
+     requires that defaults be defined properly using the now() or the
+     special value CURRENT_TIMESTAMP. These will work in all situations.
      * 'today' will no longer work as a column default; CURRENT_DATE
-       should be used instead [19]
+       should be used instead
+       
+     Note: Same description as above.
      * Dollar sign ($) is no longer allowed in operator names
-     * Dollar sign ($) can be a non-first character in identifiers [20]
+     * Dollar sign ($) can be a non-first character in identifiers
+       
+     Note: This was done to improve compatibility with other database
+     systems.
      _________________________________________________________________
    
-                                  Changes
+                          Server Operation Changes
                                       
-Server Operation
-
      * Allow IPv6 server connections (Nigel Kukard, Johan Jordaan, Bruce,
        Tom, Kurt Roeckx, Andrew Dunstan)
-     * Fix SSL to handle errors cleanly (Nathan Mueller) [21]
+     * Fix SSL to handle errors cleanly (Nathan Mueller)
+       
+     Note: In prior releases, certain rare SSL API error reports were
+     not handled correctly. This release fixes those problems.
+     gracefully.
      * SSL protocol security and performance improvements (Sean
-       Chittenden) [22]
-     * Print lock information when a deadlock is detected (Tom) [23]
+       Chittenden)
+       
+     Note: SSL key renegotiation was happening too frequently, causing
+     poor SSL performance. Also, initial key handling was improved.
+     * Print lock information when a deadlock is detected (Tom)
+       
+     Note: This allows easier debugging of deadlock situations.
      * Update "/tmp" socket mod. times regularly to avoid their removal
-       (Tom) [24]
+       (Tom)
+       
+     Note: This should help prevent "/tmp" directory cleaner
+     administration scripts from removing server socket files.
      * Enable PAM for MAC OS X (Aaron Hillegass)
-     * Make btree indexes fully WAL-safe (Tom) [25]
+     * Make btree indexes fully WAL-safe (Tom)
+       
+     Note: In prior releases, under certain rare cases, a server crash
+     could cause btree indexes to become corrupt. This release removes
+     those last few rare cases.
      * Allow btree index compaction and empty page reuse (Tom)
      * Fix inconsistent index lookups during split of first root page
-       (Tom) [26]
+       (Tom)
+       
+     Note: In prior releases, when a single-page index split into two
+     page, there was a brief period when another database session would
+     miss seeing an index entry. This failure was possible primarly on
+     multi-cpu machines. This release fixes that rare failure case.
      * Improve free space map allocation logic (Tom)
      * Preserve free space information between postmaster restarts (Tom)
-       [27]
+       
+     Note: In prior releases, the free space map was not saved when the
+     postmaster was stopped, so newly started servers has no free space
+     information. This release saves the free space map, which is loaded
+     when the server is restarted.
      * Set proper schema permissions in initdb (Peter)
      * Add start time to pg_stat_activity (Neil)
      * New code to detect corrupt disk pages; erase with
@@ -131,20 +212,32 @@ Server Operation
        detail (Tom)
      _________________________________________________________________
    
-Performance
-
+                            Performance Changes
+                                      
      * Add hashing for GROUP BY aggregates (Tom)
      * Allow nested loops to be smarter about multicolumn indexes (Tom)
      * Allow multi-key hash joins (Tom)
      * Improve constant folding (Tom)
      * Add ability to inline simple SQL functions (Tom)
-     * Reduce memory usage for queries using complex functions (Tom) [28]
-     * Improve GEQO optimizer performance (Tom) [29]
+     * Reduce memory usage for queries using complex functions (Tom)
+       
+     Note: In prior releases, functions returning allocated memory would
+     not free it until the query completed. This release allows the
+     freeing of function-allocated memory when the function call
+     completes, reducing the total memory used by functions.
+     * Improve GEQO optimizer performance (Tom)
+       
+     Note: There were several inefficiencies in the way the GEQO
+     optimizer managed potential query paths. This release fixes this.
      * Allow IN/NOT IN to be handled via hash tables (Tom)
      * Improve NOT IN (subquery) performance (Tom)
      * Allow most IN subqueries to be processed as joins (Tom)
      * Allow the postmaster to preload libraries using preload_libraries
-       (Joe) [30]
+       (Joe)
+       
+     Note: For shared libraries that require a long time to load, this
+     option is available so the library can be pre-loaded in the
+     postmaster and inherited by all database sessions.
      * Improve optimizer cost computations, particularly for subqueries
        (Tom)
      * Avoid sort when subquery ORDER BY matches upper query (Tom)
@@ -159,52 +252,106 @@ Performance
        (Henry Spencer, Tom)
      * Use bit-mapped relation sets in the optimizer (Tom)
      * Improve backend startup time (Tom)
+       
+     Note: The new network protocol requires fewer network packets to
+     start a database session.
      * Improve trigger/constraint performance (Stephan)
      * Improve speed of col IN (const, const, const, ...) (Tom)
      * Fix hash indexes which were broken in rare cases (Tom)
-     * Improve hash index concurrency and speed (Tom) [31]
+     * Improve hash index concurrency and speed (Tom)
+       
+     Note: Prior releases suffered from poor hash index performance,
+     particularly for high concurrency situations. This release fixes
+     that, and the development group is interested in reports comparing
+     btree and hash index performance.
      * Align shared buffers on 32-byte boundary for copy speed
-       improvement (Manfred Spraul) [32]
+       improvement (Manfred Spraul)
+       
+     Note: Certain CPU's perform faster data copies when addresses are
+     32-bit aligned.
      * The NUMERIC datatype has been reimplemented for better performance
-       (Tom) [33]
+       (Tom)
+       
+     Note: NUMERIC used to be stored in base-100. The new code uses
+     base-10000, for significantly better performance.
      _________________________________________________________________
    
-Server Configuration
-
+                        Server Configuration Changes
+                                      
      * Rename server parameter server_min_messages to log_min_messages
-       (Bruce) [34]
+       (Bruce)
+       
+     Note: This was done so most parameters that control the server logs
+     being with log_.
      * Rename show_*_stats to log_*_stats (Bruce)
      * Rename show_source_port to log_source_port (Bruce)
      * Rename hostname_lookup to log_hostname (Bruce)
      * Add checkpoint_warning to warn of excessive checkpointing (Bruce)
+       
+     Note: In prior releases, it was difficult to determine if
+     checkpoint was happening too frequently. This feature adds a
+     warning to the server logs when excessive checkpointing happens.
      * New read-only server parameters for localization (Tom)
      * Change debug server log messages to output as DEBUG rather than
        LOG (Bruce)
      * Prevent server log variables from being turned off by non-super
        users (Bruce)
+       
+     Note: This is a security feature so non-super-users can't disable
+     logging that was enabled by the administrator.
      * log_min_messages/client_min_messages now controls debug_* output
        (Bruce)
-     * Add Rendezvous server support (Chris Campbell)
+       
+     Note: This centralizes client debug information so all debug output
+     can be sent to either the client or server logs.
+     * Add OS X Rendezvous server support (Chris Campbell)
+       
+     Note: This allows OS X machines to query the network for available
+     PostgreSQL servers.
      * Add ability to print only slow statements using
        log_min_duration_statement (Christopher)
+       
+     Note: This is an often requested debugging feature that allows
+     administrators to see only slow queries in their server logs.
      * Allow pg_hba.conf to accept netmasks in CIDR format (Andrew
        Dunstan)
+       
+     Note: This allows administrators to merge the host IP address and
+     netmask fields into a single CIDR field in pg_hba.conf.
      * New is_superuser read-only variable (Tom)
      * New server-side parameter log_error_verbosity to control error
        detail (Tom)
+       
+     Note: This works with the new error reporting feature to supply
+     additional error information like hints, file names and line
+     numbers.
      * postgres --describe-config now dumps server config variables
        (Aizaz Ahmed, Peter)
+       
+     Note: This option is useful for administration tools that need to
+     know the configuration variable names and their minimum, maximums,
+     defaults, and descriptions.
      * Make default shared_buffers 1000 and max_connections 100, if
        possible (Tom)
+       
+     Note: Prior versions defaulted to 64 shared buffers so PostgreSQL
+     would start on even old computers. This release tests the amount of
+     shared memory supported by the hardware and sizes it accordingly.
+     Of course, users are still encouraged to evaluate their resource
+     load and size shared_buffers accordingly.
      * Add new columns in pg_settings: context, type, source, min_val,
        max_val (Joe)
      * New pg_hba.conf 'hostnossl' to prevent SSL connections (Jon
        Jensen)
+       
+     Note: In prior releases, there was no way to prevent SSL
+     connections if both the client and server supported SSL. This
+     option allows that capability.
      * Remove geqo_random_seed server parameter (Tom)
      _________________________________________________________________
    
-Queries
-
+                               Query Changes
+                                      
      * New SQL-standard information schema (Peter)
      * Add read-only transactions (Peter)
      * Add server variable regex_flavor to control regular expression
@@ -222,8 +369,8 @@ Queries
      * Change EXECUTE INTO to CREATE TABLE AS EXECUTE (Peter)
      _________________________________________________________________
    
-Object Manipulation
-
+                        Object Manipulation Changes
+                                      
      * Make CREATE SEQUENCE grammar more SQL1999 standards compliant
        (Neil)
      * Add FOR EACH STATEMENT statement-level triggers (Neil)
@@ -245,8 +392,8 @@ Object Manipulation
      * Add WITH GRANT OPTION clause to GRANT, per SQL spec (Peter)
      _________________________________________________________________
    
-Utility Commands
-
+                          Utility Command Changes
+                                      
      * Add ON COMMIT clause to CREATE TABLE for temp tables (Gavin)
      * Allow cursors outside transactions using WITH HOLD (Neil)
      * MOVE/FETCH 0 now does nothing (Bruce)
@@ -302,8 +449,8 @@ Utility Commands
      * Long options for pg_dump are now available on all platforms
      _________________________________________________________________
    
-Data Types and Functions
-
+                       Data Type and Function Changes
+                                      
      * New extra_float_digits server parameter to control float precision
        display (Pedro Ferreira, Tom)
      * Allow +1300 as a numeric timezone specifier, for FJST (Tom)
@@ -369,8 +516,8 @@ Data Types and Functions
      * Allow time to be specified as '040506' or '0405' (Tom)
      _________________________________________________________________
    
-Server-side Languages
-
+                        Server-side Language Changes
+                                      
      * Prevent PL/pgSQL crash when RETURN NEXT is used on a zero-row
        record var. (Tom)
      * Make PL/python's spi_execute interface handle NULLs properly
@@ -391,8 +538,8 @@ Server-side Languages
        the parameter type list (Jan)
      _________________________________________________________________
    
-Psql
-
+                                Psql Changes
+                                      
      * Add "\pset pager always" to always use pager (Greg)
      * Improve tab completion (Rod, Ross Reedstrom, Ian Barwick)
      * Reorder \? help into groupings (Harald Armin Massa, Bruce)
@@ -409,8 +556,8 @@ Psql
      * Long options for psql are now available on all platforms
      _________________________________________________________________
    
-Libpq
-
+                               Libpq Changes
+                                      
      * Allow PQcmdTuples() to return row counts for MOVE and FETCH (Neil)
      * Add PQfreemem() for freeing memory on Win32, suggest for NOTIFY
        (Bruce)
@@ -433,8 +580,8 @@ Libpq
        perform Bind/Execute of previously prepared statements (Tom)
      _________________________________________________________________
    
-JDBC
-
+                                JDBC Changes
+                                      
      * Allow setNull on updateable resultsets
      * Allow executeBatch on a prepared statement (Barry)
      * Support SSL connections (Barry)
@@ -442,8 +589,8 @@ JDBC
      * Add refcursor support (Nic Ferrier)
      _________________________________________________________________
    
-Miscellaneous Interfaces
-
+                      Miscellaneous Interface Changes
+                                      
      * Prevent possible memory leak or core dump during libpgtcl shutdown
        (Tom)
      * Add ecpg Informix compatibility (Michael)
@@ -453,8 +600,8 @@ Miscellaneous Interfaces
      * Move python client interface to http://www.pygresql.org (Marc)
      _________________________________________________________________
    
-Source Code
-
+                            Source Code Changes
+                                      
      * Prevent need for separate platform geometry regression result
        files (Tom)
      * Improved PPC locking primitive (Reinhard Max)
@@ -481,8 +628,8 @@ Source Code
      * Generate a compile error if spinlock code is not found (Bruce)
      _________________________________________________________________
    
-Contrib
-
+                              Contrib Changes
+                                      
      * Change dbmirror license to BSD
      * Improve earthdistance (Bruno Wolff III)
      * Portability improvements to pgcrypto (Marko Kreen)
@@ -510,8 +657,8 @@ Contrib
      * Remove array module because features now included by default (Joe)
      _________________________________________________________________
    
-Other Uncategorized
-
+                        Other Uncategorized Changes
+                                      
      * "DATESTYLE" can now be set to DMY, YMD, or MDY to specify input
        field order
      * Input date order must now be YYYY-MM-DD (with 4-digit year) or
@@ -4709,171 +4856,3 @@ The following bugs have been fixed in postgres95-beta-0.02:
      Release date: 1995-05-01
      
    Initial release.
-   
-  Notes
-  
-   [1]
-   
-   In previous releases, IN/NOT IN subqueries were joined to the upper
-   query by sequentially scanning the subquery looking for a join. The
-   7.4 code uses the same sophisticated techniques used by ordinary joins
-   and so is much faster, and is now faster than EXISTS subqueries.
-   [2]
-   
-   In previous releases, GROUP BY totals were accumulated by sequentially
-   scanning the list of groups looking for a match; the 7.4 code places
-   GROUP BY values in hash buckets so the proper match can be found much
-   quicker. This is particularly significant in speeding up queries that
-   have a large number of distinct GROUP BY values.
-   [3]
-   
-   In previous releases, hash joins could only occur on single-column
-   joins. This release allows multi-column hash joins.
-   [4]
-   
-   Prior releases evaluated ANSI join syntax only in the order specified
-   by the query; 7.4 allows full optimization of queries using ANSI join
-   syntax, meaning the optimizer considers all possible join orderings
-   and chooses the most efficient.
-   [5]
-   
-   The entire regular expression module has been replaced with a new
-   version by Henry Spencer, originally written for TCL. The code greatly
-   improves performance and supports several flavors of regular
-   expressions.
-   [6]
-   
-   Simple SQL functions can now be inlined by including their SQL in the
-   main query. This improves performance by preventing repeated calls to
-   the SQL function --- this allows simple SQL functions to behave like
-   macros.
-   [7]
-   
-   Prior releases allowed only IPv6 connections and IP data types only
-   supported IPv4 addresses. This release adds full IPv6 support in both
-   of these areas.
-   [8]
-   
-   Several people very familiar with the SSL API have overhauled our SSL
-   code to improve SSL key negotiation and error recovery.
-   [9]
-   
-   In prior releases, index pages that were left empty because of deleted
-   rows could only be reused by rows with index values similar to the
-   original rows indexed on that page. In 7.4, VACUUM records empty index
-   pages and allows them to be used for any future index rows.
-   [10]
-   
-   While prior libpq releases already supported threads, this release
-   improves thread safety by fixing some non-thread-safe code that was
-   used in the database connection routines.
-   [11]
-   
-   This new tool monitors the database statistics tables for
-   INSERT/UPDATE/DELETE activity and automatically vacuums tables when
-   needed.
-   [12]
-   
-   Many array limitations have been removed and they behave more like
-   fully-supported data types.
-   [13]
-   
-   Server-side autocommit was causing too many problems with languages
-   and applications that wanted to control their own autocommit behavior
-   so autocommit was removed from the server and added to individual
-   client API's as appropriate.
-   [14]
-   
-   In prior releases, FETCH 0 would fetch all remaining rows, and MOVE 0
-   would move to the end of the cursor.
-   [15]
-   
-   Prior releases would return the tuple count passed to the command, not
-   the actual number of rows FETCHed or MOVEd.
-   [16]
-   
-   In prior releases, a date of 10/20/03 was interpreted as a date in
-   October even if the DateStyle specified the day should be first. In
-   7.4, DateStyle is honored when converting such values and will throw
-   an error if the date is invalid for the current DateStyle.
-   [17]
-   
-   These functions were determined to be no longer useful.
-   [18]
-   
-   In prior releases, there was special code so the string 'now' was
-   interpreted at "INSERT" time and not at table creation time, but this
-   work around didn't cover all cases. Release 7.4 now requires that
-   defaults be defined properly using the now() or the special value
-   CURRENT_TIMESTAMP. These will work in all situations.
-   [19]
-   
-   Same description as above.
-   [20]
-   
-   This was done to improve compatibility with other database systems.
-   [21]
-   
-   In prior releases, certain rare SSL API error reports were not handled
-   correctly. This release fixes those problems. gracefully.
-   [22]
-   
-   SSL key renegotiation was happening too frequently, causing poor SSL
-   performance. Also, initial key handling was improved.
-   [23]
-   
-   This allows easier debugging of deadlock situations.
-   [24]
-   
-   This should help prevent "/tmp" directory cleaner administration
-   scripts from removing server socket files.
-   [25]
-   
-   In prior releases, under certain rare cases, a server crash could
-   cause btree indexes to become corrupt. This release removes those last
-   few rare cases.
-   [26]
-   
-   In prior releases, when a single-page index split into two page, there
-   was a brief period when another database session would miss seeing an
-   index entry. This failure was possible primarly on multi-cpu machines.
-   This release fixes that rare failure case.
-   [27]
-   
-   In prior releases, the free space map was not saved when the
-   postmaster was stopped, so newly started servers has no free space
-   information. This release saves the free space map, which is loaded
-   when the server is restarted.
-   [28]
-   
-   In prior releases, functions returning allocated memory would not free
-   it until the query completed. This release allows the freeing of
-   function-allocated memory when the function call completes, reducing
-   the total memory used by functions.
-   [29]
-   
-   There were several inefficiencies in the way the GEQO optimizer
-   managed potential query paths. This release fixes this.
-   [30]
-   
-   For shared libraries that require a long time to load, this option is
-   available so the library can be pre-loaded in the postmaster and
-   inherited by all database sessions.
-   [31]
-   
-   Prior releases suffered from poor hash index performance, particularly
-   for high concurrency situations. This release fixes that, and the
-   development group is interested in reports comparing btree and hash
-   index performance.
-   [32]
-   
-   Certain CPU's perform faster data copies when addresses are 32-bit
-   aligned.
-   [33]
-   
-   NUMERIC used to be stored in base-100. The new code uses base-10000,
-   for significantly better performance.
-   [34]
-   
-   This was done so most parameters that control the server logs being
-   with log_.

doc/src/sgml/release.sgml

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-$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.226 2003/10/30 20:31:24 momjian Exp $
+$Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.227 2003/10/30 20:49:47 momjian Exp $
 -->
 
 <appendix id="release">
@@ -14,7 +14,7 @@ $Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.226 2003/10/30 20:31:24 mo
 <itemizedlist>
 
 <listitem><para> IN/NOT IN subqueries are now much more efficient</para>
-  <sect3>
+  <note>
   <para>
    In previous releases, IN/NOT IN subqueries were joined to the
    upper query by sequentially scanning the subquery looking for
@@ -22,11 +22,11 @@ $Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.226 2003/10/30 20:31:24 mo
    used by ordinary joins and so is much faster, and is now faster
    than EXISTS subqueries.
   </para>
-  </sect3>
+  </note>
 </listitem>
 
 <listitem><para> Improved GROUP BY processing by using hash buckets</para>
-  <sect3>
+  <note>
   <para>
    In previous releases, GROUP BY totals were accumulated by
    sequentially scanning the list of groups looking for a match;
@@ -35,76 +35,76 @@ $Header: /cvsroot/pgsql/doc/src/sgml/release.sgml,v 1.226 2003/10/30 20:31:24 mo
    significant in speeding up queries that have a large
    number of distinct GROUP BY values.
   </para>
-  </sect3>
+  </note>
 </listitem>
 
 <listitem><para> New multi-key hash join capability</para>
-   <sect3>
+   <note>
    <para>
     In previous releases, hash joins could only occur on single-column
     joins.  This release allows multi-column hash joins.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> ANSI joins are now better optimized</para>
-   <sect3>
+   <note>
    <para>
     Prior releases evaluated ANSI join syntax only in the order
     specified by the query;  7.4 allows full optimization of
     queries using ANSI join syntax, meaning the optimizer considers
     all possible join orderings and chooses the most efficient.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> Faster and more powerful regular expression code
 </para>
-   <sect3>
+   <note>
    <para>
     The entire regular expression module has been replaced with a new
     version by Henry Spencer, originally written for TCL.  The code
     greatly improves performance and supports several flavors
     of regular expressions.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> Function-inlining for simple SQL functions</para>
-   <sect3>
+   <note>
    <para>
     Simple SQL functions can now be inlined by including their SQL
     in the main query.  This improves performance by preventing
     repeated calls to the SQL function --- this allows simple
     SQL functions to behave like macros.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> Full support for IPv6 connections and IPv6 address
 data types</para>
-   <sect3>
+   <note>
    <para>
     Prior releases allowed only IPv6 connections and IP data types only
     supported IPv4 addresses. This release adds full IPv6 support in
     both of these areas.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> Major improvements in SSL performance and
 reliability</para>
-   <sect3>
+   <note>
    <para>
     Several people very familiar with the SSL API have overhauled our
     SSL code to improve SSL key negotiation and error recovery.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> Allow free space map to efficiently reuse empty index
 pages, and other free space management improvements.</para>
-   <sect3>
+   <note>
    <para>
     In prior releases, index pages that were left empty because of
     deleted rows could only be reused by rows with index values similar
@@ -112,7 +112,7 @@ pages, and other free space management improvements.</para>
     empty index pages and allows them to be used for any future index 
     rows.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para>Implement information schema</para>
@@ -122,51 +122,51 @@ pages, and other free space management improvements.</para>
 </listitem>
 
 <listitem><para>Make cursors comply more closely with the SQL standard
-</para></glossdef>
+</para>
 </listitem>
 
 <listitem><para> New protocol improves connection speed/reliability,
 and adds error codes, status information, a binary protocol, error
-reporting verbosity, and cleaner startup packets.</para></glossdef>
+reporting verbosity, and cleaner startup packets.</para>
 </listitem>
           
-<listitem><glossdef><para> Allow cursors to exist outside transactions, 
+<listitem><para> Allow cursors to exist outside transactions, 
 also called holdable cursors
 </para>
 </listitem>
 
-<listitem><glossdef><para> libpq and ecpg are now fully thread-safe with
+<listitem><para> libpq and ecpg are now fully thread-safe with
 --enable-thread-safety</para>
-   <sect3>
+   <note>
    <para>
     While prior libpq releases already supported threads, this release
     improves thread safety by fixing some non-thread-safe code that
     was used in the database connection routines.
-   </para>
-   </sect3>
+  </para>
+   </note>
 </listitem>
 
 <listitem><para> New version of full text indexing in /contrib/tsearch2</para>
 </listitem>
 
 <listitem><para> New autovacuum tool in /contrib</para>
-   <sect3>
+   <note>
    <para>
     This new tool monitors the database statistics tables for
     INSERT/UPDATE/DELETE activity and automatically vacuums tables when
     needed.
    </para>
-   </sect3>
+   </note>
 </listitem>
 
 <listitem><para> Array handling has been improved and moved into the main
 server</para>
-   <sect3>
+   <note>
    <para>
     Many array limitations have been removed and they behave more like
     fully-supported data types.
    </para>
-   </sect3>
+   </note>
 </listitem>
 </itemizedlist></para></sect2>
 
@@ -179,14 +179,14 @@ required for those wishing to migrate data from any previous release.</para>
 <itemizedlist>
      <listitem><para> The server-side autocommit setting was removed and reimplemented
        in client applications and languages.</para>
-          <sect3>
-	  <para>
+          <note>
+   <para>
 	   Server-side autocommit was causing too many problems with
 	   languages and applications that wanted to control their own 
 	   autocommit behavior so autocommit was removed from the server
 	   and added to individual client API's as appropriate.
-	  </para>
-	  </sect3>
+  </para>
+	  </note>
      </listitem>
      <listitem><para> Error message wording has changed substantially in this release,
        and error codes have been added.</para></listitem>
@@ -194,21 +194,21 @@ required for those wishing to migrate data from any previous release.</para>
      <listitem><para> A number of server variables have been renamed for
      clarity, primarily those related to logging</para></listitem>
      <listitem><para> MOVE/FETCH 0 now does nothing</para>
-        <sect3>
-	<para>
+        <note>
+   <para>
 	 In prior releases, FETCH 0 would fetch all remaining rows, and
 	 MOVE 0 would move to the end of the cursor.
-	</para>
-	</sect3>
+  </para>
+	</note>
      </listitem>
      <listitem><para> MOVE/FETCH now returns the actual number of rows moved/fetched, or zero
         if at the beginning/end of the cursor</para>
-	   <sect3>
-	   <para>
+	   <note>
+   <para>
 	    Prior releases would return the tuple count passed to the
 	    command, not the actual number of rows FETCHed or MOVEd.
-	   </para>
-	   </sect3>
+  </para>
+	   </note>
      </listitem>
      <listitem><para> COPY now can process carriage-return and
            carriage-return/line-feed end-of-line terminated files.</para></listitem>
@@ -219,29 +219,29 @@ required for those wishing to migrate data from any previous release.</para>
        <type>VARCHAR(n)</type> / <type>TEXT</type></para></listitem>
      <listitem><para> <function>FLOAT(p)</function> now measures 'p' in bits, not digits</para></listitem>
      <listitem><para> Ambiguous date values now must match the ordering specified by DateStyle</para>
-        <sect3>
-	<para>
+        <note>
+   <para>
 	 In prior releases, a date of <literal>10/20/03</> was
 	 interpreted as a date in October even if the
 	 <varname>DateStyle</> specified the day should be first. In
 	 7.4, <varname>DateStyle</> is honored when converting such
 	 values and will throw an error if the date is invalid for the
 	 current <varname>DateStyle</>.
-	</para>
-	</sect3>
+  </para>
+	</note>
      </listitem>
      <listitem><para> The <function>oidrand()</function>, <function>oidsrand()</function>,
 	and <function>userfntest()</function> functions have been removed.</para>
-	   <sect3>
-	   <para>
+	   <note>
+   <para>
 	    These functions were determined to be no longer useful.
-	   </para>
-	   </sect3>
+  </para>
+	   </note>
      </listitem>
      <listitem><para> <literal>'now'</literal> will no longer work as a column default; <function>now()</> or
         <function>CURRENT_TIMESTAMP</> should be used instead</para>
-	   <sect3>
-	   <para>
+	   <note>
+   <para>
 	    In prior releases, there was special code so the string
 	    <literal>'now'</literal> was interpreted at
 	    <command>INSERT</> time and not at table creation time, but
@@ -250,25 +250,25 @@ required for those wishing to migrate data from any previous release.</para>
 	    <function>now()</> or the special value
 	    <function>CURRENT_TIMESTAMP</>. These will work in all
 	    situations.
-	   </para>
-	   </sect3>
+  </para>
+	   </note>
      </listitem>
      <listitem><para> <literal>'today'</literal> will no longer work as a column default; <function>CURRENT_DATE</> 
         should be used instead</para>
-	   <sect3>
-	   <para>
+	   <note>
+   <para>
 	    Same description as above.
-	   </para>
-	   </sect3>
+  </para>
+	   </note>
      </listitem>
      <listitem><para> Dollar sign (<literal>$</>) is no longer allowed in operator names</para></listitem>
      <listitem><para> Dollar sign (<literal>$</>) can be a non-first character in identifiers</para>
-        <sect3>
-	<para>
+        <note>
+   <para>
 	 This was done to improve compatibility with other database
 	 systems.
-	</para>
-	</sect3>
+  </para>
+	</note>
      </listitem>
 </itemizedlist></para></sect2>
 
@@ -277,68 +277,68 @@ required for those wishing to migrate data from any previous release.</para>
 <listitem><para>Allow IPv6 server connections (Nigel Kukard, Johan Jordaan, Bruce, Tom, Kurt
   Roeckx, Andrew Dunstan)</para></listitem>
 <listitem><para>Fix SSL to handle errors cleanly (Nathan Mueller)
-   <sect3>
+   <note>
    <para>
     In prior releases, certain rare SSL API error reports were not
     handled correctly.  This release fixes those problems.
     gracefully.
    </para>
-   </sect3>
+   </note>
    </para></listitem>
 <listitem><para>SSL protocol security and performance improvements (Sean Chittenden)</para>
-   <sect3>
+   <note>
    <para>
     SSL key renegotiation was happening too frequently, causing poor SSL
     performance.  Also, initial key handling was improved.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Print lock information when a deadlock is detected (Tom)</para>
-   <sect3>
+   <note>
    <para>
     This allows easier debugging of deadlock situations.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Update <filename>/tmp</filename> socket mod. times regularly to avoid their removal (Tom)</para>
-   <sect3>
+   <note>
    <para>
     This should help prevent <filename>/tmp</filename> directory cleaner
     administration scripts from removing server socket files.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Enable PAM for MAC OS X (Aaron Hillegass)</para></listitem>
 <listitem><para>Make btree indexes fully WAL-safe (Tom)</para>
-   <sect3>
+   <note>
    <para>
     In prior releases, under certain rare cases, a server crash could
     cause btree indexes to become corrupt. This release removes those
     last few rare cases.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Allow btree index compaction and empty page reuse (Tom)</para></listitem>
 <listitem><para>Fix inconsistent index lookups during split of first root page (Tom)</para>
-   <sect3>
+   <note>
    <para>
     In prior releases, when a single-page index split into two page,
     there was a brief period when another database session would miss
     seeing an index entry. This failure was possible primarly on
     multi-cpu machines.  This release fixes that rare failure case.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Improve free space map allocation logic (Tom)</para></listitem>
 <listitem><para>Preserve free space information between postmaster restarts (Tom)</para>
-   <sect3>
+   <note>
    <para>
     In prior releases, the free space map was not saved when the
     postmaster was stopped, so newly started servers has no free space
     information. This release saves the free space map, which is loaded
     when the server is restarted.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Set proper schema permissions in initdb (Peter)</para></listitem>
 <listitem><para>Add start time to pg_stat_activity (Neil)</para></listitem>
@@ -361,34 +361,34 @@ required for those wishing to migrate data from any previous release.</para>
 <listitem><para>Improve constant folding (Tom)</para></listitem>
 <listitem><para>Add ability to inline simple SQL functions (Tom)</para></listitem>
 <listitem><para>Reduce memory usage for queries using complex functions (Tom)</para>
-   <sect3>
+   <note>
    <para>
     In prior releases, functions returning allocated memory would
     not free it until the query completed. This release allows the
     freeing of function-allocated memory when the function call
     completes, reducing the total memory used by functions.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Improve GEQO optimizer performance (Tom)</para>
-   <sect3>
+   <note>
    <para>
     There were several inefficiencies in the way the GEQO optimizer
     managed potential query paths.  This release fixes this.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Allow IN/NOT IN to be handled via hash tables (Tom)</para></listitem>
 <listitem><para>Improve NOT IN (subquery) performance (Tom)</para></listitem>
 <listitem><para>Allow most IN subqueries to be processed as joins (Tom)</para></listitem>
 <listitem><para>Allow the postmaster to preload libraries using preload_libraries (Joe)</para>
-   <sect3>
+   <note>
    <para>
     For shared libraries that require a long time to load, this option
     is available so the library can be pre-loaded in the postmaster and
     inherited by all database sessions.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Improve optimizer cost computations, particularly for subqueries (Tom)</para></listitem>
 <listitem><para>Avoid sort when subquery ORDER BY matches upper query (Tom)</para></listitem>
@@ -400,41 +400,41 @@ required for those wishing to migrate data from any previous release.</para>
 <listitem><para>Use faster and more powerful regular expression code from TCL (Henry Spencer, Tom)</para></listitem>
 <listitem><para>Use bit-mapped relation sets in the optimizer (Tom)</para></listitem>
 <listitem><para>Improve backend startup time (Tom)</para>
-   <sect3>
+   <note>
    <para>
     The new network protocol requires fewer network packets to start a
     database session.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Improve trigger/constraint performance (Stephan)</para></listitem>
 <listitem><para>Improve speed of col IN (const, const, const, ...) (Tom)</para></listitem>
 <listitem><para>Fix hash indexes which were broken in rare cases (Tom)</para></listitem>
 <listitem><para>Improve hash index concurrency and speed (Tom)</para>
-   <sect3>
+   <note>
    <para>
     Prior releases suffered from poor hash index performance,
     particularly for high concurrency situations. This release fixes
     that, and the development group is interested in reports comparing
     btree and hash index performance.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Align shared buffers on 32-byte boundary for copy speed improvement (Manfred Spraul)</para>
-   <sect3>
+   <note>
    <para>
     Certain CPU's perform faster data copies when addresses are 32-bit
     aligned.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>The NUMERIC datatype has been reimplemented for better performance (Tom)</para>
-   <sect3>
+   <note>
    <para>
     NUMERIC used to be stored in base-100. The new code uses base-10000,
     for significantly better performance.
    </para>
-   </sect3>
+   </note>
    </listitem>
 </itemizedlist></sect2>
 
@@ -442,88 +442,88 @@ required for those wishing to migrate data from any previous release.</para>
 
 <itemizedlist>
 <listitem><para>Rename server parameter server_min_messages to log_min_messages (Bruce)</para>
-   <sect3>
+   <note>
    <para>
     This was done so most parameters that control the server logs being
     with <literal>log_</>.
    </para>
-   </sect3>
+   </note>
 </listitem>
 <listitem><para>Rename show_*_stats to log_*_stats (Bruce)</para></listitem>
 <listitem><para>Rename show_source_port to log_source_port (Bruce)</para></listitem>
 <listitem><para>Rename hostname_lookup to log_hostname (Bruce)</para></listitem>
 <listitem><para>Add checkpoint_warning to warn of excessive checkpointing (Bruce)</para>
-   <sect3>
+   <note>
    <para>
     In prior releases, it was difficult to determine if checkpoint was
     happening too frequently. This feature adds a warning to the server
     logs when excessive checkpointing happens.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>New read-only server parameters for localization (Tom)</para></listitem>
 <listitem><para>Change debug server log messages to output as DEBUG rather than LOG (Bruce)</para></listitem>
 <listitem><para>Prevent server log variables from being turned off by non-super users (Bruce)</para>
-   <sect3>
+   <note>
    <para>
     This is a security feature so non-super-users can't disable logging
     that was enabled by the administrator.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>log_min_messages/client_min_messages now controls debug_* output (Bruce)</para>
-   <sect3>
+   <note>
    <para>
     This centralizes client debug information so all debug output can
     be sent to either the client or server logs.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Add OS X Rendezvous server support (Chris Campbell)</para>
-   <sect3>
+   <note>
    <para>
     This allows OS X machines to query the network for available
     PostgreSQL servers.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Add ability to print only slow statements using log_min_duration_statement
   (Christopher)</para>
-     <sect3>
+     <note>
      <para>
       This is an often requested debugging feature that allows administrators to
-      see only slow queries in their server logs.</para>
+      see only slow queries in their server logs.
      </para>
-     </sect3>
+     </note>
      </listitem>
 <listitem><para>Allow pg_hba.conf to accept netmasks in CIDR format (Andrew Dunstan)</para>
-   <sect3>
+   <note>
    <para>
     This allows administrators to merge the host IP address and netmask
     fields into a single CIDR field in pg_hba.conf.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>New is_superuser read-only variable (Tom)</para></listitem>
 <listitem><para>New server-side parameter log_error_verbosity to control error detail (Tom)</para>
-   <sect3>
+   <note>
    <para>
     This works with the new error reporting feature to supply additional
     error information like hints, file names and line numbers.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>postgres --describe-config now dumps server config variables (Aizaz Ahmed, Peter)</para>
-   <sect3>
+   <note>
    <para>
     This option is useful for administration tools that need to know the
     configuration variable names and their minimum, maximums, defaults,
     and descriptions.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Make default shared_buffers 1000 and max_connections 100, if possible (Tom)</para>
-   <sect3>
+   <note>
    <para>
     Prior versions defaulted to 64 shared buffers so PostgreSQL would
     start on even old computers. This release tests the amount of shared
@@ -531,17 +531,17 @@ required for those wishing to migrate data from any previous release.</para>
     course, users are still encouraged to evaluate their resource load
     and size shared_buffers accordingly.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Add new columns in pg_settings: context, type, source, min_val, max_val (Joe)</para></listitem>
 <listitem><para>New pg_hba.conf 'hostnossl' to prevent SSL connections (Jon Jensen)
-   <sect3>
+   <note>
    <para>
     In prior releases, there was no way to prevent SSL connections if
     both the client and server supported SSL. This option allows that
     capability.
    </para>
-   </sect3>
+   </note>
    </listitem>
 <listitem><para>Remove geqo_random_seed server parameter (Tom)</para></listitem>
 </itemizedlist></sect2>