Logical replication

- Add PUBLICATION catalogs and DDL
- Add SUBSCRIPTION catalog and DDL
- Define logical replication protocol and output plugin
- Add logical replication workers

From: Petr Jelinek <petr@2ndquadrant.com>
Reviewed-by: Steve Singer <steve@ssinger.info>
Reviewed-by: Andres Freund <andres@anarazel.de>
Reviewed-by: Erik Rijkers <er@xs4all.nl>
Reviewed-by: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>

doc/src/sgml/config.sgml

@@ -3411,6 +3411,47 @@ ANY <replaceable class="parameter">num_sync</replaceable> ( <replaceable class="
 
      </variablelist>
     </sect2>
+
+    <sect2 id="runtime-config-replication-subscriber">
+     <title>Subscribers</title>
+
+     <para>
+      These settings control the behavior of a logical replication subscriber.
+      Their values on the publisher are irrelevant.
+     </para>
+
+     <para>
+      Note that <varname>wal_receiver_timeout</varname> and
+      <varname>wal_retrieve_retry_interval</varname> configuration parameters
+      affect the logical replication workers as well.
+     </para>
+
+     <variablelist>
+
+     <varlistentry id="guc-max-logical-replication-workers" xreflabel="max_logical_replication_workers">
+      <term><varname>max_logical_replication_workers</varname> (<type>int</type>)
+      <indexterm>
+       <primary><varname>max_logical_replication_workers</> configuration parameter</primary>
+      </indexterm>
+      </term>
+      <listitem>
+       <para>
+        Specifies maximum number of logical replication workers. This includes
+        both apply workers and table synchronization workers.
+       </para>
+       <para>
+        Logical replication workers are taken from the pool defined by
+        <varname>max_worker_processes</varname>.
+       </para>
+       <para>
+        The default value is 4.
+       </para>
+      </listitem>
+     </varlistentry>
+
+     </variablelist>
+    </sect2>
+
    </sect1>
 
    <sect1 id="runtime-config-query">

doc/src/sgml/filelist.sgml

@@ -50,6 +50,7 @@
 <!ENTITY config        SYSTEM "config.sgml">
 <!ENTITY user-manag    SYSTEM "user-manag.sgml">
 <!ENTITY wal           SYSTEM "wal.sgml">
+<!ENTITY logical-replication    SYSTEM "logical-replication.sgml">
 
 <!-- programmer's guide -->
 <!ENTITY bgworker   SYSTEM "bgworker.sgml">

doc/src/sgml/func.sgml

@@ -18762,7 +18762,7 @@ postgres=# SELECT * FROM pg_xlogfile_name_offset(pg_stop_backup());
       </row>
 
       <row>
-       <entry>
+       <entry id="pg-replication-origin-advance">
         <indexterm>
          <primary>pg_replication_origin_advance</primary>
         </indexterm>

doc/src/sgml/monitoring.sgml

@@ -308,6 +308,14 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
       </entry>
      </row>
 
+     <row>
+      <entry><structname>pg_stat_subscription</><indexterm><primary>pg_stat_subscription</primary></indexterm></entry>
+      <entry>At least one row per subscription, showing information about
+       the subscription workers.
+       See <xref linkend="pg-stat-subscription"> for details.
+      </entry>
+     </row>
+
      <row>
       <entry><structname>pg_stat_ssl</><indexterm><primary>pg_stat_ssl</primary></indexterm></entry>
       <entry>One row per connection (regular and replication), showing information about
@@ -1545,6 +1553,72 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
    connected server.
   </para>
 
+  <table id="pg-stat-subscription" xreflabel="pg_stat_subscription">
+   <title><structname>pg_stat_subscription</structname> View</title>
+   <tgroup cols="3">
+    <thead>
+    <row>
+      <entry>Column</entry>
+      <entry>Type</entry>
+      <entry>Description</entry>
+     </row>
+    </thead>
+
+   <tbody>
+    <row>
+     <entry><structfield>subid</></entry>
+     <entry><type>oid</></entry>
+     <entry>OID of the subscription</entry>
+    </row>
+    <row>
+     <entry><structfield>subname</></entry>
+     <entry><type>text</></entry>
+     <entry>Name of the subscription</entry>
+    </row>
+    <row>
+     <entry><structfield>pid</></entry>
+     <entry><type>integer</></entry>
+     <entry>Process ID of the subscription worker process</entry>
+    </row>
+    <row>
+     <entry><structfield>received_lsn</></entry>
+     <entry><type>pg_lsn</></entry>
+     <entry>Last transaction log position received, the initial value of
+      this field being 0</entry>
+    </row>
+    <row>
+     <entry><structfield>last_msg_send_time</></entry>
+     <entry><type>timestamp with time zone</></entry>
+     <entry>Send time of last message received from origin WAL sender</entry>
+    </row>
+    <row>
+     <entry><structfield>last_msg_receipt_time</></entry>
+     <entry><type>timestamp with time zone</></entry>
+     <entry>Receipt time of last message received from origin WAL sender
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>latest_end_lsn</></entry>
+     <entry><type>pg_lsn</></entry>
+     <entry>Last transaction log position reported to origin WAL sender
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>latest_end_time</></entry>
+     <entry><type>timestamp with time zone</></entry>
+     <entry>Time of last transaction log position reported to origin WAL
+      sender</entry>
+    </row>
+   </tbody>
+   </tgroup>
+  </table>
+
+  <para>
+   The <structname>pg_stat_subscription</structname> view will contain one
+   row per subscription for main worker (with null PID if the worker is
+   not running).
+  </para>
+
   <table id="pg-stat-ssl-view" xreflabel="pg_stat_ssl">
    <title><structname>pg_stat_ssl</structname> View</title>
    <tgroup cols="3">

doc/src/sgml/postgres.sgml

@@ -160,6 +160,7 @@
   &monitoring;
   &diskusage;
   &wal;
+  &logical-replication;
   &regress;
 
  </part>

doc/src/sgml/ref/allfiles.sgml

@@ -26,11 +26,13 @@ Complete list of usable sgml source files in this directory.
 <!ENTITY alterOperatorClass SYSTEM "alter_opclass.sgml">
 <!ENTITY alterOperatorFamily SYSTEM "alter_opfamily.sgml">
 <!ENTITY alterPolicy        SYSTEM "alter_policy.sgml">
+<!ENTITY alterPublication   SYSTEM "alter_publication.sgml">
 <!ENTITY alterRole          SYSTEM "alter_role.sgml">
 <!ENTITY alterRule          SYSTEM "alter_rule.sgml">
 <!ENTITY alterSchema        SYSTEM "alter_schema.sgml">
 <!ENTITY alterServer        SYSTEM "alter_server.sgml">
 <!ENTITY alterSequence      SYSTEM "alter_sequence.sgml">
+<!ENTITY alterSubscription  SYSTEM "alter_subscription.sgml">
 <!ENTITY alterSystem        SYSTEM "alter_system.sgml">
 <!ENTITY alterTable         SYSTEM "alter_table.sgml">
 <!ENTITY alterTableSpace    SYSTEM "alter_tablespace.sgml">
@@ -72,11 +74,13 @@ Complete list of usable sgml source files in this directory.
 <!ENTITY createOperatorClass SYSTEM "create_opclass.sgml">
 <!ENTITY createOperatorFamily SYSTEM "create_opfamily.sgml">
 <!ENTITY createPolicy       SYSTEM "create_policy.sgml">
+<!ENTITY createPublication  SYSTEM "create_publication.sgml">
 <!ENTITY createRole         SYSTEM "create_role.sgml">
 <!ENTITY createRule         SYSTEM "create_rule.sgml">
 <!ENTITY createSchema       SYSTEM "create_schema.sgml">
 <!ENTITY createSequence     SYSTEM "create_sequence.sgml">
 <!ENTITY createServer       SYSTEM "create_server.sgml">
+<!ENTITY createSubscription SYSTEM "create_subscription.sgml">
 <!ENTITY createTable        SYSTEM "create_table.sgml">
 <!ENTITY createTableAs      SYSTEM "create_table_as.sgml">
 <!ENTITY createTableSpace   SYSTEM "create_tablespace.sgml">
@@ -116,11 +120,13 @@ Complete list of usable sgml source files in this directory.
 <!ENTITY dropOperatorFamily  SYSTEM "drop_opfamily.sgml">
 <!ENTITY dropOwned          SYSTEM "drop_owned.sgml">
 <!ENTITY dropPolicy         SYSTEM "drop_policy.sgml">
+<!ENTITY dropPublication    SYSTEM "drop_publication.sgml">
 <!ENTITY dropRole           SYSTEM "drop_role.sgml">
 <!ENTITY dropRule           SYSTEM "drop_rule.sgml">
 <!ENTITY dropSchema         SYSTEM "drop_schema.sgml">
 <!ENTITY dropSequence       SYSTEM "drop_sequence.sgml">
 <!ENTITY dropServer         SYSTEM "drop_server.sgml">
+<!ENTITY dropSubscription   SYSTEM "drop_subscription.sgml">
 <!ENTITY dropTable          SYSTEM "drop_table.sgml">
 <!ENTITY dropTableSpace     SYSTEM "drop_tablespace.sgml">
 <!ENTITY dropTransform      SYSTEM "drop_transform.sgml">

doc/src/sgml/ref/alter_publication.sgml

+<!--
+doc/src/sgml/ref/alter_publication.sgml
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-ALTERPUBLICATION">
+ <indexterm zone="sql-alterpublication">
+  <primary>ALTER PUBLICATION</primary>
+ </indexterm>
+
+ <refmeta>
+  <refentrytitle>ALTER PUBLICATION</refentrytitle>
+  <manvolnum>7</manvolnum>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+  <refname>ALTER PUBLICATION</refname>
+  <refpurpose>change the definition of a publication</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+<synopsis>
+ALTER PUBLICATION <replaceable class="PARAMETER">name</replaceable> WITH ( <replaceable class="PARAMETER">option</replaceable> [, ... ] )
+
+<phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
+
+      PUBLISH INSERT | NOPUBLISH INSERT
+    | PUBLISH UPDATE | NOPUBLISH UPDATE
+    | PUBLISH DELETE | NOPUBLISH DELETE
+
+ALTER PUBLICATION <replaceable class="PARAMETER">name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
+ALTER PUBLICATION <replaceable class="PARAMETER">name</replaceable> ADD TABLE <replaceable class="PARAMETER">table_name</replaceable> [, ...]
+ALTER PUBLICATION <replaceable class="PARAMETER">name</replaceable> SET TABLE <replaceable class="PARAMETER">table_name</replaceable> [, ...]
+ALTER PUBLICATION <replaceable class="PARAMETER">name</replaceable> DROP TABLE <replaceable class="PARAMETER">table_name</replaceable> [, ...]
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+  <title>Description</title>
+
+  <para>
+   The first variant of this command listed in the synopsis can change
+   all of the publication properties specified in
+   <xref linkend="sql-createpublication">.  Properties not mentioned in the
+   command retain their previous settings.  Database superusers can change any
+   of these settings for any role.
+  </para>
+
+  <para>
+   To alter the owner, you must also be a direct or indirect member of the
+   new owning role. The new owner has to be a superuser
+  </para>
+
+  <para>
+   The other variants of this command deal with the table membership of the
+   publication.  The <literal>SET TABLE</literal> clause will replace the
+   list of tables in the publication with the specified one.
+   The <literal>ADD TABLE</literal> and
+   <literal>DROP TABLE</literal> will add and remove one or more tables from
+   the publication.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><replaceable class="parameter">name</replaceable></term>
+    <listitem>
+     <para>
+      The name of an existing publication whose definition is to be altered.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>PUBLISH INSERT</literal></term>
+    <term><literal>NOPUBLISH INSERT</literal></term>
+    <term><literal>PUBLISH UPDATE</literal></term>
+    <term><literal>NOPUBLISH UPDATE</literal></term>
+    <term><literal>PUBLISH DELETE</literal></term>
+    <term><literal>NOPUBLISH DELETE</literal></term>
+    <listitem>
+     <para>
+      These clauses alter properties originally set by
+      <xref linkend="SQL-CREATEPUBLICATION">.  See there for more information.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><replaceable class="parameter">table_name</replaceable></term>
+    <listitem>
+     <para>
+      Name of an existing table.
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+ </refsect1>
+
+ <refsect1>
+  <title>Examples</title>
+
+  <para>
+   Change the publication to not publish inserts:
+<programlisting>
+ALTER PUBLICATION noinsert WITH (NOPUBLISH INSERT);
+</programlisting>
+  </para>
+
+  <para>
+   Add some tables to the publication:
+<programlisting>
+ALTER PUBLICATION mypublication ADD TABLE users, departments;
+</programlisting>
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Compatibility</title>
+
+  <para>
+   <command>ALTER PUBLICATION</command> is a <productname>PostgreSQL</>
+   extension.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>See Also</title>
+
+  <simplelist type="inline">
+   <member><xref linkend="sql-createpublication"></member>
+   <member><xref linkend="sql-droppublication"></member>
+  </simplelist>
+ </refsect1>
+</refentry>

doc/src/sgml/ref/alter_subscription.sgml

+<!--
+doc/src/sgml/ref/alter_subscription.sgml
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-ALTERSUBSCRIPTION">
+ <indexterm zone="sql-altersubscription">
+  <primary>ALTER SUBSCRIPTION</primary>
+ </indexterm>
+
+ <refmeta>
+  <refentrytitle>ALTER SUBSCRIPTION</refentrytitle>
+  <manvolnum>7</manvolnum>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+  <refname>ALTER SUBSCRIPTION</refname>
+  <refpurpose>change the definition of a subscription</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+<synopsis>
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> WITH ( <replaceable class="PARAMETER">option</replaceable> [, ... ] ) ]
+
+<phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
+
+  SLOT NAME = slot_name
+
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> CONNECTION 'conninfo'
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> SET PUBLICATION publication_name [, ...]
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> ENABLE
+ALTER SUBSCRIPTION <replaceable class="PARAMETER">name</replaceable> DISABLE
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+  <title>Description</title>
+
+  <para>
+   <command>ALTER SUBSCRIPTION</command> can change most of the subscription
+   properties that can be specified
+   in <xref linkend="sql-createsubscription">.
+  </para>
+
+  <para>
+   To alter the owner, you must also be a direct or indirect member of the
+   new owning role. The new owner has to be a superuser
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><replaceable class="parameter">name</replaceable></term>
+    <listitem>
+     <para>
+      The name of a subscription whose properties are to be altered.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>CONNECTION '<replaceable class="parameter">conninfo</replaceable>'</literal></term>
+    <term><literal>SET PUBLICATION <replaceable class="parameter">publication_name</replaceable></literal></term>
+    <term><literal>SLOT NAME = <replaceable class="parameter">slot_name</replaceable></literal></term>
+    <listitem>
+     <para>
+      These clauses alter properties originally set by
+      <xref linkend="SQL-CREATESUBSCRIPTION">.  See there for more
+      information.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>ENABLE</literal></term>
+    <listitem>
+     <para>
+      Enables the previously disabled subscription, starting the logical
+      replication worker at the end of transaction.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>DISABLE</literal></term>
+    <listitem>
+     <para>
+      Disables the running subscription, stopping the logical replication
+      worker at the end of transaction.
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+ </refsect1>
+
+ <refsect1>
+  <title>Examples</title>
+
+  <para>
+   Change the publication subscribed by a subscription to
+   <literal>insert_only</literal>:
+<programlisting>
+ALTER SUBSCRIPTION mysub SET PUBLICATION insert_only;
+</programlisting>
+  </para>
+
+  <para>
+   Disable (stop) the subscription:
+<programlisting>
+ALTER SUBSCRIPTION mysub DISABLE;
+</programlisting>
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Compatibility</title>
+
+  <para>
+   <command>ALTER SUBSCRIPTION</command> is a <productname>PostgreSQL</>
+   extension.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>See Also</title>
+
+  <simplelist type="inline">
+   <member><xref linkend="sql-createsubscription"></member>
+   <member><xref linkend="sql-dropsubscription"></member>
+   <member><xref linkend="sql-createpublication"></member>
+   <member><xref linkend="sql-alterpublication"></member>
+  </simplelist>
+ </refsect1>
+</refentry>

doc/src/sgml/ref/create_publication.sgml

+<!--
+doc/src/sgml/ref/create_publication.sgml
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-CREATEPUBLICATION">
+ <indexterm zone="sql-createpublication">
+  <primary>CREATE PUBLICATION</primary>
+ </indexterm>
+
+ <refmeta>
+  <refentrytitle>CREATE PUBLICATION</refentrytitle>
+  <manvolnum>7</manvolnum>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+  <refname>CREATE PUBLICATION</refname>
+  <refpurpose>define a new publication</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+<synopsis>
+CREATE PUBLICATION <replaceable class="parameter">name</replaceable>
+    [ FOR TABLE <replaceable class="parameter">table_name</replaceable> [, ...]
+      | FOR ALL TABLES ]
+    [ WITH ( <replaceable class="parameter">option</replaceable> [, ... ] ) ]
+
+<phrase>where <replaceable class="parameter">option</replaceable> can be:</phrase>
+
+      PUBLISH INSERT | NOPUBLISH INSERT
+    | PUBLISH UPDATE | NOPUBLISH UPDATE
+    | PUBLISH DELETE | NOPUBLISH DELETE
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+  <title>Description</title>
+
+  <para>
+   <command>CREATE PUBLICATION</command> adds a new publication
+   into the current database.  The publication name must be distinct from
+   the name of any existing publication in the current database.
+  </para>
+
+  <para>
+   A publication is essentially a group of tables whose data changes are
+   intended to be replicated through logical replication.  See
+   <xref linkend="logical-replication-publication"> for details about how
+   publications fit into the logical replication setup.
+   </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><replaceable class="parameter">name</replaceable></term>
+    <listitem>
+     <para>
+      The name of the new publication.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>FOR TABLE</literal></term>
+    <listitem>
+     <para>
+      Specifies a list of tables to add to the publication.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>FOR ALL TABLES</literal></term>
+    <listitem>
+     <para>
+      Marks the publication as one that replicates changes for all tables in
+      the database, including tables created in the future.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>PUBLISH INSERT</literal></term>
+    <term><literal>NOPUBLISH INSERT</literal></term>
+    <listitem>
+     <para>
+      These clauses determine whether the new publication will send
+      the <command>INSERT</command> operations to the subscribers.
+      <literal>PUBLISH INSERT</literal> is the default.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>PUBLISH UPDATE</literal></term>
+    <term><literal>NOPUBLISH UPDATE</literal></term>
+    <listitem>
+     <para>
+      These clauses determine whether the new publication will send
+      the <command>UPDATE</command> operations to the subscribers.
+      <literal>PUBLISH UPDATE</literal> is the default.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>PUBLISH DELETE</literal></term>
+    <term><literal>NOPUBLISH DELETE</literal></term>
+    <listitem>
+     <para>
+      These clauses determine whether the new publication will send
+      the <command>DELETE</command> operations to the subscribers.
+      <literal>PUBLISH DELETE</literal> is the default.
+     </para>
+    </listitem>
+   </varlistentry>
+
+  </variablelist>
+ </refsect1>
+
+ <refsect1>
+  <title>Notes</title>
+
+  <para>
+   If neither <literal>FOR TABLE</literal> nor <literal>FOR ALL
+   TABLES</literal> is specified, then the publication starts out with an
+   empty set of tables.  That is useful if tables are to be added later.
+  </para>
+
+  <para>
+   The creation of a publication does not start replication.  It only defines
+   a grouping and filtering logic for future subscribers.
+  </para>
+
+  <para>
+   To create a publication, the invoking user must have the
+   <literal>CREATE</> privilege for the current database.
+   (Of course, superusers bypass this check.)
+  </para>
+
+  <para>
+   To add a table to a publication, the invoking user must have
+   <command>SELECT</command> privilege on given table.  The
+   <command>FOR ALL TABLES</command> clause requires superuser.
+  </para>
+
+  <para>
+   The tables added to a publication that publishes <command>UPDATE</command>
+   and/or <command>DELETE</command> operations must have
+   <literal>REPLICA IDENTITY</> defined.  Otherwise those operations will be
+   disallowed on those tables.
+  </para>
+
+  <para>
+   For an <command>INSERT ... ON CONFLICT</> command, the publication will
+   publish the operation that actually results from the command.  So depending
+   of the outcome, it may be published as either <command>INSERT</command> or
+   <command>UPDATE</command>, or it may not be published at all.
+  </para>
+
+  <para>
+   <command>TRUNCATE</command> and other <acronym>DDL</acronym> operations
+   are not published.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Examples</title>
+
+  <para>
+   Create a simple publication that just publishes all DML for tables in it:
+<programlisting>
+CREATE PUBLICATION mypublication;
+</programlisting>
+  </para>
+
+  <para>
+   Create an insert-only publication:
+<programlisting>
+CREATE PUBLICATION insert_only WITH (NOPUBLISH UPDATE, NOPUBLISH DELETE);
+</programlisting>
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Compatibility</title>
+
+  <para>
+   <command>CREATE PUBLICATION</command> is a <productname>PostgreSQL</>
+   extension.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>See Also</title>
+
+  <simplelist type="inline">
+   <member><xref linkend="sql-alterpublication"></member>
+   <member><xref linkend="sql-droppublication"></member>
+  </simplelist>
+ </refsect1>
+</refentry>

doc/src/sgml/ref/create_subscription.sgml

+<!--
+doc/src/sgml/ref/create_subscription.sgml
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-CREATESUBSCRIPTION">
+ <indexterm zone="sql-createsubscription">
+  <primary>CREATE SUBSCRIPTION</primary>
+ </indexterm>
+
+ <refmeta>
+  <refentrytitle>CREATE SUBSCRIPTION</refentrytitle>
+  <manvolnum>7</manvolnum>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+  <refname>CREATE SUBSCRIPTION</refname>
+  <refpurpose>define a new subscription</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+<synopsis>
+CREATE SUBSCRIPTION <replaceable class="PARAMETER">subscription_name</replaceable> CONNECTION 'conninfo' PUBLICATION { publication_name [, ...] } [ WITH ( <replaceable class="PARAMETER">option</replaceable> [, ... ] ) ]
+
+<phrase>where <replaceable class="PARAMETER">option</replaceable> can be:</phrase>
+
+    | ENABLED | DISABLED
+    | CREATE SLOT | NOCREATE SLOT
+    | SLOT NAME = slot_name
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+  <title>Description</title>
+
+  <para>
+   <command>CREATE SUBSCRIPTION</command> adds a new subscription for a
+   current database.  The subscription name must be distinct from the name of
+   any existing subscription in the database.
+  </para>
+
+  <para>
+   The subscription represents a replication connection to the publisher.  As
+   such this command does not only add definitions in the local catalogs but
+   also creates a replication slot on the publisher.
+  </para>
+
+  <para>
+   A logical replication worker will be started to replicate data for the new
+   subscription at the commit of the transaction where this command is run.
+  </para>
+
+  <para>
+   Additional info about subscriptions and logical replication as a whole
+   can is available at <xref linkend="logical-replication-subscription"> and
+   <xref linkend="logical-replication">.
+  </para>
+
+ </refsect1>
+
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><replaceable class="parameter">subscription_name</replaceable></term>
+    <listitem>
+     <para>
+      The name of the new subscription.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>CONNECTION '<replaceable class="parameter">conninfo</replaceable>'</literal></term>
+    <listitem>
+     <para>
+      The connection string to the publisher.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>PUBLICATION <replaceable class="parameter">publication_name</replaceable></literal></term>
+    <listitem>
+     <para>
+      Name(s) of the publications on the publisher to subscribe to.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>ENABLED</literal></term>
+    <term><literal>DISABLED</literal></term>
+    <listitem>
+     <para>
+      Specifies whether the subscription should be actively replicating or
+      if it should be just setup but not started yet.  Note that the
+      replication slot as described above is created in either case.
+      <literal>ENABLED</literal> is the default.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>CREATE SLOT</literal></term>
+    <term><literal>NOCREATE SLOT</literal></term>
+    <listitem>
+     <para>
+      Specifies whether the command should create the replication slot on the
+      publisher. <literal>CREATE SLOT</literal> is the default.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>SLOT NAME = <replaceable class="parameter">slot_name</replaceable></literal></term>
+    <listitem>
+     <para>
+      Name of the replication slot to use. The default behavior is to use
+      <literal>subscription_name</> for slot name.
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+ </refsect1>
+
+ <refsect1>
+  <title>Examples</title>
+
+  <para>
+   Create a subscription to a remote server that replicates tables in
+   the publications <literal>mypubclication</literal> and
+   <literal>insert_only</literal> and starts replicating immediately on
+   commit:
+<programlisting>
+CREATE SUBSCRIPTION mysub
+         CONNECTION 'host=192.168.1.50 port=5432 user=foo dbname=foodb password=foopass'
+        PUBLICATION mypublication, insert_only;
+</programlisting>
+  </para>
+
+  <para>
+   Create a subscription to a remote server that replicates tables in
+   the <literal>insert_only</literal> publication and does not start replicating
+   until enabled at a later time.
+<programlisting>
+CREATE SUBSCRIPTION mysub
+         CONNECTION 'host=192.168.1.50 port=5432 user=foo dbname=foodb password=foopass'
+        PUBLICATION insert_only
+               WITH (DISABLED);
+</programlisting>
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Compatibility</title>
+
+  <para>
+   <command>CREATE SUBSCRIPTION</command> is a <productname>PostgreSQL</>
+   extension.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>See Also</title>
+
+  <simplelist type="inline">
+   <member><xref linkend="sql-altersubscription"></member>
+   <member><xref linkend="sql-dropsubscription"></member>
+   <member><xref linkend="sql-createpublication"></member>
+   <member><xref linkend="sql-alterpublication"></member>
+  </simplelist>
+ </refsect1>
+</refentry>

doc/src/sgml/ref/drop_publication.sgml

+<!--
+doc/src/sgml/ref/drop_publication.sgml
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-DROPPUBLICATION">
+ <indexterm zone="sql-droppublication">
+  <primary>DROP PUBLICATION</primary>
+ </indexterm>
+
+ <refmeta>
+  <refentrytitle>DROP PUBLICATION</refentrytitle>
+  <manvolnum>7</manvolnum>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+  <refname>DROP PUBLICATION</refname>
+  <refpurpose>remove a publication</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+<synopsis>
+DROP PUBLICATION [ IF EXISTS ] <replaceable class="PARAMETER">name</replaceable> [, ...] [ CASCADE | RESTRICT ]
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+  <title>Description</title>
+
+  <para>
+   <command>DROP PUBLICATION</command> removes an existing publication from
+   the database.
+  </para>
+
+  <para>
+   A publication can only be dropped by its owner or a superuser.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><literal>IF EXISTS</literal></term>
+    <listitem>
+     <para>
+      Do not throw an error if the extension does not exist. A notice is issued
+      in this case.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><replaceable class="parameter">name</replaceable></term>
+    <listitem>
+     <para>
+      The name of an existing publication.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><literal>CASCADE</literal></term>
+    <term><literal>RESTRICT</literal></term>
+
+    <listitem>
+     <para>
+      These key words do not have any effect, since there are no dependencies
+      on publications.
+     </para>
+    </listitem>
+   </varlistentry>
+  </variablelist>
+ </refsect1>
+
+ <refsect1>
+  <title>Examples</title>
+
+  <para>
+   Drop a publication:
+<programlisting>
+DROP PUBLICATION mypublication;
+</programlisting>
+  </para>
+
+ </refsect1>
+
+ <refsect1>
+  <title>Compatibility</title>
+
+  <para>
+   <command>DROP PUBLICATION</command> is a <productname>PostgreSQL</>
+   extension.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>See Also</title>
+
+  <simplelist type="inline">
+   <member><xref linkend="sql-createpublication"></member>
+   <member><xref linkend="sql-alterpublication"></member>
+  </simplelist>
+ </refsect1>
+</refentry>

doc/src/sgml/ref/drop_subscription.sgml

+<!--
+doc/src/sgml/ref/drop_subscription.sgml
+PostgreSQL documentation
+-->
+
+<refentry id="SQL-DROPSUBSCRIPTION">
+ <indexterm zone="sql-dropsubscription">
+  <primary>DROP SUBSCRIPTION</primary>
+ </indexterm>
+
+ <refmeta>
+  <refentrytitle>DROP SUBSCRIPTION</refentrytitle>
+  <manvolnum>7</manvolnum>
+  <refmiscinfo>SQL - Language Statements</refmiscinfo>
+ </refmeta>
+
+ <refnamediv>
+  <refname>DROP SUBSCRIPTION</refname>
+  <refpurpose>remove a subscription</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+<synopsis>
+DROP SUBSCRIPTION [ IF EXISTS ] <replaceable class="parameter">name</replaceable> [ <replaceable class="parameter">DROP SLOT</replaceable> | <replaceable class="parameter">NODROP SLOT</replaceable> ]
+</synopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+  <title>Description</title>
+
+  <para>
+   <command>DROP SUBSCRIPTION</command> removes a subscription from the
+   database cluster.
+  </para>
+
+  <para>
+   A subscription can only be dropped by a superuser.
+  </para>
+
+  <para>
+   The replication worker associated with the subscription will not stop until
+   after the transaction that issued this command has committed.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>Parameters</title>
+
+  <variablelist>
+   <varlistentry>
+    <term><replaceable class="parameter">name</replaceable></term>
+    <listitem>
+     <para>
+      The name of a subscription to be dropped.
+     </para>
+    </listitem>
+   </varlistentry>
+
+   <varlistentry>
+    <term><replaceable class="parameter">DROP SLOT</replaceable></term>
+    <term><replaceable class="parameter">NODROP SLOT</replaceable></term>
+    <listitem>
+     <para>
+      Specifies whether to drop the replication slot on the publisher.  The
+      default is
+      <literal>DROP SLOT</literal>.
+     </para>
+
+     <para>
+      If the publisher is not reachable when the subscription is to be
+      dropped, then it is useful to specify <literal>NODROP SLOT</literal>.
+      But the replication slot on the publisher will then have to be removed
+      manually.
+     </para>
+    </listitem>
+   </varlistentry>
+
+  </variablelist>
+ </refsect1>
+
+ <refsect1>
+  <title>Examples</title>
+
+  <para>
+   Drop a subscription:
+<programlisting>
+DROP SUBSCRIPTION mysub;
+</programlisting>
+  </para>
+
+ </refsect1>
+
+ <refsect1>
+  <title>Compatibility</title>
+
+  <para>
+   <command>DROP SUBSCRIPTION</command> is a <productname>PostgreSQL</>
+   extension.
+  </para>
+ </refsect1>
+
+ <refsect1>
+  <title>See Also</title>
+
+  <simplelist type="inline">
+   <member><xref linkend="sql-createsubscription"></member>
+   <member><xref linkend="sql-altersubscription"></member>
+  </simplelist>
+ </refsect1>
+</refentry>

doc/src/sgml/ref/pg_dump.sgml

@@ -755,6 +755,15 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--include-subscriptions</option></term>
+      <listitem>
+       <para>
+        Include logical replication subscriptions in the dump.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--inserts</option></term>
       <listitem>
@@ -789,6 +798,18 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--no-create-subscription-slots</option></term>
+      <listitem>
+       <para>
+        When dumping logical replication subscriptions,
+        generate <command>CREATE SUBSCRIPTION</command> commands that do not
+        create the remote replication slot.  That way, the dump can be
+        restored without requiring network access to the remote servers.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--no-security-labels</option></term>
       <listitem>

doc/src/sgml/ref/psql-ref.sgml

@@ -1600,6 +1600,34 @@ testdb=>
         </listitem>
       </varlistentry>
 
+      <varlistentry>
+        <term><literal>\dRp[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
+        <listitem>
+        <para>
+        Lists replication publications.
+        If <replaceable class="parameter">pattern</replaceable> is
+        specified, only those publications whose names match the pattern are
+        listed.
+        If <literal>+</literal> is appended to the command name, the tables
+        associated with each publication are shown as well.
+        </para>
+        </listitem>
+      </varlistentry>
+
+      <varlistentry>
+        <term><literal>\dRs[+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
+        <listitem>
+        <para>
+        Lists replication subscriptions.
+        If <replaceable class="parameter">pattern</replaceable> is
+        specified, only those subscriptions whose names match the pattern are
+        listed.
+        If <literal>+</literal> is appended to the command name, additional
+        properties of the subscriptions are shown.
+        </para>
+        </listitem>
+      </varlistentry>
+
       <varlistentry>
         <term><literal>\dT[S+] [ <link linkend="APP-PSQL-patterns"><replaceable class="parameter">pattern</replaceable></link> ]</literal></term>
         <listitem>

doc/src/sgml/reference.sgml

@@ -54,11 +54,13 @@
    &alterOperatorClass;
    &alterOperatorFamily;
    &alterPolicy;
+   &alterPublication;
    &alterRole;
    &alterRule;
    &alterSchema;
    &alterSequence;
    &alterServer;
+   &alterSubscription;
    &alterSystem;
    &alterTable;
    &alterTableSpace;
@@ -100,11 +102,13 @@
    &createOperatorClass;
    &createOperatorFamily;
    &createPolicy;
+   &createPublication;
    &createRole;
    &createRule;
    &createSchema;
    &createSequence;
    &createServer;
+   &createSubscription;
    &createTable;
    &createTableAs;
    &createTableSpace;
@@ -144,11 +148,13 @@
    &dropOperatorFamily;
    &dropOwned;
    &dropPolicy;
+   &dropPublication;
    &dropRole;
    &dropRule;
    &dropSchema;
    &dropSequence;
    &dropServer;
+   &dropSubscription;
    &dropTable;
    &dropTableSpace;
    &dropTSConfig;

src/Makefile

@@ -22,6 +22,7 @@ SUBDIRS = \
 	include \
 	interfaces \
 	backend/replication/libpqwalreceiver \
+	backend/replication/pgoutput \
 	fe_utils \
 	bin \
 	pl \

src/backend/access/transam/xact.c

@@ -42,6 +42,7 @@
 #include "miscadmin.h"
 #include "pgstat.h"
 #include "replication/logical.h"
+#include "replication/logicallauncher.h"
 #include "replication/origin.h"
 #include "replication/syncrep.h"
 #include "replication/walsender.h"
@@ -2135,6 +2136,7 @@ CommitTransaction(void)
 	AtEOXact_HashTables(true);
 	AtEOXact_PgStat(true);
 	AtEOXact_Snapshot(true);
+	AtCommit_ApplyLauncher();
 	pgstat_report_xact_timestamp(0);
 
 	CurrentResourceOwner = NULL;

src/backend/catalog/Makefile

@@ -14,8 +14,9 @@ OBJS = catalog.o dependency.o heap.o index.o indexing.o namespace.o aclchk.o \
        objectaccess.o objectaddress.o partition.o pg_aggregate.o pg_collation.o \
        pg_constraint.o pg_conversion.o \
        pg_depend.o pg_enum.o pg_inherits.o pg_largeobject.o pg_namespace.o \
-       pg_operator.o pg_proc.o pg_range.o pg_db_role_setting.o pg_shdepend.o \
-       pg_type.o storage.o toasting.o
+       pg_operator.o pg_proc.o pg_publication.o pg_range.o \
+	   pg_db_role_setting.o pg_shdepend.o pg_subscription.o pg_type.o \
+	   storage.o toasting.o
 
 BKIFILES = postgres.bki postgres.description postgres.shdescription
 
@@ -42,7 +43,7 @@ POSTGRES_BKI_SRCS = $(addprefix $(top_srcdir)/src/include/catalog/,\
 	pg_foreign_table.h pg_policy.h pg_replication_origin.h \
 	pg_default_acl.h pg_init_privs.h pg_seclabel.h pg_shseclabel.h \
 	pg_collation.h pg_partitioned_table.h pg_range.h pg_transform.h \
-	pg_sequence.h \
+	pg_sequence.h pg_publication.h pg_publication_rel.h pg_subscription.h \
 	toasting.h indexing.h \
     )
 

src/backend/catalog/aclchk.c

@@ -45,6 +45,7 @@
 #include "catalog/pg_operator.h"
 #include "catalog/pg_opfamily.h"
 #include "catalog/pg_proc.h"
+#include "catalog/pg_subscription.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_type.h"
 #include "catalog/pg_ts_config.h"
@@ -3390,6 +3391,10 @@ static const char *const not_owner_msg[MAX_ACL_KIND] =
 	gettext_noop("must be owner of event trigger %s"),
 	/* ACL_KIND_EXTENSION */
 	gettext_noop("must be owner of extension %s"),
+	/* ACL_KIND_PUBLICATION */
+	gettext_noop("must be owner of publication %s"),
+	/* ACL_KIND_SUBSCRIPTION */
+	gettext_noop("must be owner of subscription %s"),
 };
 
 
@@ -5071,6 +5076,58 @@ pg_extension_ownercheck(Oid ext_oid, Oid roleid)
 	return has_privs_of_role(roleid, ownerId);
 }
 
+/*
+ * Ownership check for an publication (specified by OID).
+ */
+bool
+pg_publication_ownercheck(Oid pub_oid, Oid roleid)
+{
+	HeapTuple	tuple;
+	Oid			ownerId;
+
+	/* Superusers bypass all permission checking. */
+	if (superuser_arg(roleid))
+		return true;
+
+	tuple = SearchSysCache1(PUBLICATIONOID, ObjectIdGetDatum(pub_oid));
+	if (!HeapTupleIsValid(tuple))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("publication with OID %u does not exist", pub_oid)));
+
+	ownerId = ((Form_pg_publication) GETSTRUCT(tuple))->pubowner;
+
+	ReleaseSysCache(tuple);
+
+	return has_privs_of_role(roleid, ownerId);
+}
+
+/*
+ * Ownership check for an subscription (specified by OID).
+ */
+bool
+pg_subscription_ownercheck(Oid sub_oid, Oid roleid)
+{
+	HeapTuple	tuple;
+	Oid			ownerId;
+
+	/* Superusers bypass all permission checking. */
+	if (superuser_arg(roleid))
+		return true;
+
+	tuple = SearchSysCache1(SUBSCRIPTIONOID, ObjectIdGetDatum(sub_oid));
+	if (!HeapTupleIsValid(tuple))
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("subscription with OID %u does not exist", sub_oid)));
+
+	ownerId = ((Form_pg_subscription) GETSTRUCT(tuple))->subowner;
+
+	ReleaseSysCache(tuple);
+
+	return has_privs_of_role(roleid, ownerId);
+}
+
 /*
  * Check whether specified role has CREATEROLE privilege (or is a superuser)
  *

src/backend/catalog/catalog.c

@@ -36,6 +36,7 @@
 #include "catalog/pg_shdepend.h"
 #include "catalog/pg_shdescription.h"
 #include "catalog/pg_shseclabel.h"
+#include "catalog/pg_subscription.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/toasting.h"
 #include "miscadmin.h"
@@ -227,7 +228,8 @@ IsSharedRelation(Oid relationId)
 		relationId == SharedSecLabelRelationId ||
 		relationId == TableSpaceRelationId ||
 		relationId == DbRoleSettingRelationId ||
-		relationId == ReplicationOriginRelationId)
+		relationId == ReplicationOriginRelationId ||
+		relationId == SubscriptionRelationId)
 		return true;
 	/* These are their indexes (see indexing.h) */
 	if (relationId == AuthIdRolnameIndexId ||
@@ -245,7 +247,9 @@ IsSharedRelation(Oid relationId)
 		relationId == TablespaceNameIndexId ||
 		relationId == DbRoleSettingDatidRolidIndexId ||
 		relationId == ReplicationOriginIdentIndex ||
-		relationId == ReplicationOriginNameIndex)
+		relationId == ReplicationOriginNameIndex ||
+		relationId == SubscriptionObjectIndexId ||
+		relationId == SubscriptionNameIndexId)
 		return true;
 	/* These are their toast tables and toast indexes (see toasting.h) */
 	if (relationId == PgShdescriptionToastTable ||

src/backend/catalog/dependency.c

@@ -48,7 +48,10 @@
 #include "catalog/pg_opfamily.h"
 #include "catalog/pg_policy.h"
 #include "catalog/pg_proc.h"
+#include "catalog/pg_publication.h"
+#include "catalog/pg_publication_rel.h"
 #include "catalog/pg_rewrite.h"
+#include "catalog/pg_subscription.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_transform.h"
 #include "catalog/pg_trigger.h"
@@ -64,6 +67,7 @@
 #include "commands/extension.h"
 #include "commands/policy.h"
 #include "commands/proclang.h"
+#include "commands/publicationcmds.h"
 #include "commands/schemacmds.h"
 #include "commands/seclabel.h"
 #include "commands/sequence.h"
@@ -164,6 +168,9 @@ static const Oid object_classes[] = {
 	ExtensionRelationId,		/* OCLASS_EXTENSION */
 	EventTriggerRelationId,		/* OCLASS_EVENT_TRIGGER */
 	PolicyRelationId,			/* OCLASS_POLICY */
+	PublicationRelationId,		/* OCLASS_PUBLICATION */
+	PublicationRelRelationId,	/* OCLASS_PUBLICATION_REL */
+	SubscriptionRelationId,		/* OCLASS_SUBSCRIPTION */
 	TransformRelationId			/* OCLASS_TRANSFORM */
 };
 
@@ -1244,6 +1251,14 @@ doDeletion(const ObjectAddress *object, int flags)
 			RemovePolicyById(object->objectId);
 			break;
 
+		case OCLASS_PUBLICATION:
+			RemovePublicationById(object->objectId);
+			break;
+
+		case OCLASS_PUBLICATION_REL:
+			RemovePublicationRelById(object->objectId);
+			break;
+
 		case OCLASS_TRANSFORM:
 			DropTransformById(object->objectId);
 			break;
@@ -2404,6 +2419,15 @@ getObjectClass(const ObjectAddress *object)
 		case PolicyRelationId:
 			return OCLASS_POLICY;
 
+		case PublicationRelationId:
+			return OCLASS_PUBLICATION;
+
+		case PublicationRelRelationId:
+			return OCLASS_PUBLICATION_REL;
+
+		case SubscriptionRelationId:
+			return OCLASS_SUBSCRIPTION;
+
 		case TransformRelationId:
 			return OCLASS_TRANSFORM;
 	}

src/backend/catalog/objectaddress.c

@@ -45,7 +45,10 @@
 #include "catalog/pg_operator.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_policy.h"
+#include "catalog/pg_publication.h"
+#include "catalog/pg_publication_rel.h"
 #include "catalog/pg_rewrite.h"
+#include "catalog/pg_subscription.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_transform.h"
 #include "catalog/pg_trigger.h"
@@ -450,6 +453,30 @@ static const ObjectPropertyType ObjectProperty[] =
 		Anum_pg_type_typacl,
 		ACL_KIND_TYPE,
 		true
+	},
+	{
+		PublicationRelationId,
+		PublicationObjectIndexId,
+		PUBLICATIONOID,
+		PUBLICATIONNAME,
+		Anum_pg_publication_pubname,
+		InvalidAttrNumber,
+		Anum_pg_publication_pubowner,
+		InvalidAttrNumber,
+		-1,
+		true
+	},
+	{
+		SubscriptionRelationId,
+		SubscriptionObjectIndexId,
+		SUBSCRIPTIONOID,
+		SUBSCRIPTIONNAME,
+		Anum_pg_subscription_subname,
+		InvalidAttrNumber,
+		Anum_pg_subscription_subowner,
+		InvalidAttrNumber,
+		-1,
+		true
 	}
 };
 
@@ -653,6 +680,18 @@ static const struct object_type_map
 	{
 		"policy", OBJECT_POLICY
 	},
+	/* OCLASS_PUBLICATION */
+	{
+		"publication", OBJECT_PUBLICATION
+	},
+	/* OCLASS_PUBLICATION_REL */
+	{
+		"publication relation", OBJECT_PUBLICATION_REL
+	},
+	/* OCLASS_SUBSCRIPTION */
+	{
+		"subscription", OBJECT_SUBSCRIPTION
+	},
 	/* OCLASS_TRANSFORM */
 	{
 		"transform", OBJECT_TRANSFORM
@@ -688,6 +727,9 @@ static ObjectAddress get_object_address_opf_member(ObjectType objtype,
 
 static ObjectAddress get_object_address_usermapping(List *objname,
 							   List *objargs, bool missing_ok);
+static ObjectAddress get_object_address_publication_rel(List *objname,
+								   List *objargs, Relation *relation,
+								   bool missing_ok);
 static ObjectAddress get_object_address_defacl(List *objname, List *objargs,
 						  bool missing_ok);
 static const ObjectPropertyType *get_object_property_data(Oid class_id);
@@ -812,6 +854,8 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 			case OBJECT_FOREIGN_SERVER:
 			case OBJECT_EVENT_TRIGGER:
 			case OBJECT_ACCESS_METHOD:
+			case OBJECT_PUBLICATION:
+			case OBJECT_SUBSCRIPTION:
 				address = get_object_address_unqualified(objtype,
 														 objname, missing_ok);
 				break;
@@ -926,6 +970,10 @@ get_object_address(ObjectType objtype, List *objname, List *objargs,
 				address = get_object_address_usermapping(objname, objargs,
 														 missing_ok);
 				break;
+			case OBJECT_PUBLICATION_REL:
+				address = get_object_address_publication_rel(objname, objargs,
+															 &relation,
+															 missing_ok);
 			case OBJECT_DEFACL:
 				address = get_object_address_defacl(objname, objargs,
 													missing_ok);
@@ -1091,6 +1139,12 @@ get_object_address_unqualified(ObjectType objtype,
 			case OBJECT_EVENT_TRIGGER:
 				msg = gettext_noop("event trigger name cannot be qualified");
 				break;
+			case OBJECT_PUBLICATION:
+				msg = gettext_noop("publication name cannot be qualified");
+				break;
+			case OBJECT_SUBSCRIPTION:
+				msg = gettext_noop("subscription name cannot be qualified");
+				break;
 			default:
 				elog(ERROR, "unrecognized objtype: %d", (int) objtype);
 				msg = NULL;		/* placate compiler */
@@ -1156,6 +1210,16 @@ get_object_address_unqualified(ObjectType objtype,
 			address.objectId = get_event_trigger_oid(name, missing_ok);
 			address.objectSubId = 0;
 			break;
+		case OBJECT_PUBLICATION:
+			address.classId = PublicationRelationId;
+			address.objectId = get_publication_oid(name, missing_ok);
+			address.objectSubId = 0;
+			break;
+		case OBJECT_SUBSCRIPTION:
+			address.classId = SubscriptionRelationId;
+			address.objectId = get_subscription_oid(name, missing_ok);
+			address.objectSubId = 0;
+			break;
 		default:
 			elog(ERROR, "unrecognized objtype: %d", (int) objtype);
 			/* placate compiler, which doesn't know elog won't return */
@@ -1743,6 +1807,51 @@ get_object_address_usermapping(List *objname, List *objargs, bool missing_ok)
 	return address;
 }
 
+/*
+ * Find the ObjectAddress for a publication relation.  The objname parameter
+ * is the relation name; objargs contains the publication name.
+ */
+static ObjectAddress
+get_object_address_publication_rel(List *objname, List *objargs,
+								   Relation *relation, bool missing_ok)
+{
+	ObjectAddress address;
+	char	   *pubname;
+	Publication *pub;
+
+	ObjectAddressSet(address, PublicationRelRelationId, InvalidOid);
+
+	*relation = relation_openrv_extended(makeRangeVarFromNameList(objname),
+										 AccessShareLock, missing_ok);
+	if (!relation)
+		return address;
+
+	/* fetch publication name from input list */
+	pubname = strVal(linitial(objargs));
+
+	/* Now look up the pg_publication tuple */
+	pub = GetPublicationByName(pubname, missing_ok);
+	if (!pub)
+		return address;
+
+	/* Find the publication relation mapping in syscache. */
+	address.objectId =
+		GetSysCacheOid2(PUBLICATIONRELMAP,
+						ObjectIdGetDatum(RelationGetRelid(*relation)),
+						ObjectIdGetDatum(pub->oid));
+	if (!OidIsValid(address.objectId))
+	{
+		if (!missing_ok)
+			ereport(ERROR,
+					(errcode(ERRCODE_UNDEFINED_OBJECT),
+					 errmsg("publication relation \"%s\" in publication \"%s\" does not exist",
+							RelationGetRelationName(*relation), pubname)));
+		return address;
+	}
+
+	return address;
+}
+
 /*
  * Find the ObjectAddress for a default ACL.
  */
@@ -2002,6 +2111,7 @@ pg_get_object_address(PG_FUNCTION_ARGS)
 		case OBJECT_DOMCONSTRAINT:
 		case OBJECT_CAST:
 		case OBJECT_USER_MAPPING:
+		case OBJECT_PUBLICATION_REL:
 		case OBJECT_DEFACL:
 		case OBJECT_TRANSFORM:
 			if (list_length(args) != 1)
@@ -2183,6 +2293,16 @@ check_object_ownership(Oid roleid, ObjectType objtype, ObjectAddress address,
 									format_type_be(targettypeid))));
 			}
 			break;
+		case OBJECT_PUBLICATION:
+			if (!pg_publication_ownercheck(address.objectId, roleid))
+				aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_PUBLICATION,
+							   NameListToString(objname));
+			break;
+		case OBJECT_SUBSCRIPTION:
+			if (!pg_subscription_ownercheck(address.objectId, roleid))
+				aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_SUBSCRIPTION,
+							   NameListToString(objname));
+			break;
 		case OBJECT_TRANSFORM:
 			{
 				TypeName   *typename = (TypeName *) linitial(objname);
@@ -3191,6 +3311,41 @@ getObjectDescription(const ObjectAddress *object)
 				break;
 			}
 
+		case OCLASS_PUBLICATION:
+			{
+				appendStringInfo(&buffer, _("publication %s"),
+								 get_publication_name(object->objectId));
+				break;
+			}
+
+		case OCLASS_PUBLICATION_REL:
+			{
+				HeapTuple	tup;
+				char	   *pubname;
+				Form_pg_publication_rel	prform;
+
+				tup = SearchSysCache1(PUBLICATIONREL,
+									  ObjectIdGetDatum(object->objectId));
+				if (!HeapTupleIsValid(tup))
+					elog(ERROR, "cache lookup failed for publication table %u",
+						 object->objectId);
+
+				prform = (Form_pg_publication_rel) GETSTRUCT(tup);
+				pubname = get_publication_name(prform->prpubid);
+
+				appendStringInfo(&buffer, _("publication table %s in publication %s"),
+								 get_rel_name(prform->prrelid), pubname);
+				ReleaseSysCache(tup);
+				break;
+			}
+
+		case OCLASS_SUBSCRIPTION:
+			{
+				appendStringInfo(&buffer, _("subscription %s"),
+								 get_subscription_name(object->objectId));
+				break;
+			}
+
 		default:
 			appendStringInfo(&buffer, "unrecognized object %u %u %d",
 							 object->classId,
@@ -3677,6 +3832,18 @@ getObjectTypeDescription(const ObjectAddress *object)
 			appendStringInfoString(&buffer, "access method");
 			break;
 
+		case OCLASS_PUBLICATION:
+			appendStringInfoString(&buffer, "publication");
+			break;
+
+		case OCLASS_PUBLICATION_REL:
+			appendStringInfoString(&buffer, "publication table");
+			break;
+
+		case OCLASS_SUBSCRIPTION:
+			appendStringInfoString(&buffer, "subscription");
+			break;
+
 		default:
 			appendStringInfo(&buffer, "unrecognized %u", object->classId);
 			break;
@@ -4648,6 +4815,58 @@ getObjectIdentityParts(const ObjectAddress *object,
 			}
 			break;
 
+		case OCLASS_PUBLICATION:
+			{
+				char	   *pubname;
+
+				pubname = get_publication_name(object->objectId);
+				appendStringInfoString(&buffer,
+									   quote_identifier(pubname));
+				if (objname)
+					*objname = list_make1(pubname);
+				break;
+			}
+
+		case OCLASS_PUBLICATION_REL:
+			{
+				HeapTuple	tup;
+				char	   *pubname;
+				Form_pg_publication_rel	prform;
+
+				tup = SearchSysCache1(PUBLICATIONREL,
+									  ObjectIdGetDatum(object->objectId));
+				if (!HeapTupleIsValid(tup))
+					elog(ERROR, "cache lookup failed for publication table %u",
+						 object->objectId);
+
+				prform = (Form_pg_publication_rel) GETSTRUCT(tup);
+				pubname = get_publication_name(prform->prpubid);
+
+				appendStringInfo(&buffer, _("publication table %s in publication %s"),
+								 get_rel_name(prform->prrelid), pubname);
+
+				if (objname)
+				{
+					getRelationIdentity(&buffer, prform->prrelid, objname);
+					*objargs = list_make1(pubname);
+				}
+
+				ReleaseSysCache(tup);
+				break;
+			}
+
+		case OCLASS_SUBSCRIPTION:
+			{
+				char	   *subname;
+
+				subname = get_subscription_name(object->objectId);
+				appendStringInfoString(&buffer,
+									   quote_identifier(subname));
+				if (objname)
+					*objname = list_make1(subname);
+				break;
+			}
+
 		default:
 			appendStringInfo(&buffer, "unrecognized object %u %u %d",
 							 object->classId,

src/backend/catalog/pg_shdepend.c

@@ -39,6 +39,7 @@
 #include "catalog/pg_opfamily.h"
 #include "catalog/pg_proc.h"
 #include "catalog/pg_shdepend.h"
+#include "catalog/pg_subscription.h"
 #include "catalog/pg_tablespace.h"
 #include "catalog/pg_ts_config.h"
 #include "catalog/pg_ts_dict.h"
@@ -53,7 +54,9 @@
 #include "commands/extension.h"
 #include "commands/policy.h"
 #include "commands/proclang.h"
+#include "commands/publicationcmds.h"
 #include "commands/schemacmds.h"
+#include "commands/subscriptioncmds.h"
 #include "commands/tablecmds.h"
 #include "commands/typecmds.h"
 #include "storage/lmgr.h"
@@ -1406,6 +1409,14 @@ shdepReassignOwned(List *roleids, Oid newrole)
 					AlterEventTriggerOwner_oid(sdepForm->objid, newrole);
 					break;
 
+				case PublicationRelationId:
+					AlterPublicationOwner_oid(sdepForm->objid, newrole);
+					break;
+
+				case SubscriptionRelationId:
+					AlterSubscriptionOwner_oid(sdepForm->objid, newrole);
+					break;
+
 					/* Generic alter owner cases */
 				case CollationRelationId:
 				case ConversionRelationId:

src/backend/catalog/pg_subscription.c

+/*-------------------------------------------------------------------------
+ *
+ * pg_subscription.c
+ *		replication subscriptions
+ *
+ * Copyright (c) 2016, PostgreSQL Global Development Group
+ *
+ * IDENTIFICATION
+ *		src/backend/catalog/pg_subscription.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres.h"
+
+#include "miscadmin.h"
+
+#include "access/genam.h"
+#include "access/heapam.h"
+#include "access/htup_details.h"
+
+#include "catalog/pg_type.h"
+#include "catalog/pg_subscription.h"
+
+#include "nodes/makefuncs.h"
+
+#include "utils/array.h"
+#include "utils/builtins.h"
+#include "utils/fmgroids.h"
+#include "utils/syscache.h"
+
+
+static List *textarray_to_stringlist(ArrayType *textarray);
+
+/*
+ * Fetch the subscription from the syscache.
+ */
+Subscription *
+GetSubscription(Oid subid, bool missing_ok)
+{
+	HeapTuple		tup;
+	Subscription   *sub;
+	Form_pg_subscription	subform;
+	Datum			datum;
+	bool			isnull;
+
+	tup = SearchSysCache1(SUBSCRIPTIONOID, ObjectIdGetDatum(subid));
+
+	if (!HeapTupleIsValid(tup))
+	{
+		if (missing_ok)
+			return NULL;
+
+		elog(ERROR, "cache lookup failed for subscription %u", subid);
+	}
+
+	subform = (Form_pg_subscription) GETSTRUCT(tup);
+
+	sub = (Subscription *) palloc(sizeof(Subscription));
+	sub->oid = subid;
+	sub->dbid = subform->subdbid;
+	sub->name = pstrdup(NameStr(subform->subname));
+	sub->owner = subform->subowner;
+	sub->enabled = subform->subenabled;
+
+	/* Get conninfo */
+	datum = SysCacheGetAttr(SUBSCRIPTIONOID,
+							tup,
+							Anum_pg_subscription_subconninfo,
+							&isnull);
+	Assert(!isnull);
+	sub->conninfo = pstrdup(TextDatumGetCString(datum));
+
+	/* Get slotname */
+	datum = SysCacheGetAttr(SUBSCRIPTIONOID,
+							tup,
+							Anum_pg_subscription_subslotname,
+							&isnull);
+	Assert(!isnull);
+	sub->slotname = pstrdup(NameStr(*DatumGetName(datum)));
+
+	/* Get publications */
+	datum = SysCacheGetAttr(SUBSCRIPTIONOID,
+							tup,
+							Anum_pg_subscription_subpublications,
+							&isnull);
+	Assert(!isnull);
+	sub->publications = textarray_to_stringlist(DatumGetArrayTypeP(datum));
+
+	ReleaseSysCache(tup);
+
+	return sub;
+}
+
+/*
+ * Return number of subscriptions defined in given database.
+ * Used by dropdb() to check if database can indeed be dropped.
+ */
+int
+CountDBSubscriptions(Oid dbid)
+{
+	int				nsubs = 0;
+	Relation		rel;
+	ScanKeyData		scankey;
+	SysScanDesc		scan;
+	HeapTuple		tup;
+
+	rel = heap_open(SubscriptionRelationId, RowExclusiveLock);
+
+	ScanKeyInit(&scankey,
+				Anum_pg_subscription_subdbid,
+				BTEqualStrategyNumber, F_OIDEQ,
+				ObjectIdGetDatum(dbid));
+
+	scan = systable_beginscan(rel, InvalidOid, false,
+							  NULL, 1, &scankey);
+
+	while (HeapTupleIsValid(tup = systable_getnext(scan)))
+		nsubs++;
+
+	systable_endscan(scan);
+
+	heap_close(rel, NoLock);
+
+	return nsubs;
+}
+
+/*
+ * Free memory allocated by subscription struct.
+ */
+void
+FreeSubscription(Subscription *sub)
+{
+	pfree(sub->name);
+	pfree(sub->conninfo);
+	pfree(sub->slotname);
+	list_free_deep(sub->publications);
+	pfree(sub);
+}
+
+/*
+ * get_subscription_oid - given a subscription name, look up the OID
+ *
+ * If missing_ok is false, throw an error if name not found.  If true, just
+ * return InvalidOid.
+ */
+Oid
+get_subscription_oid(const char *subname, bool missing_ok)
+{
+	Oid			oid;
+
+	oid = GetSysCacheOid2(SUBSCRIPTIONNAME, MyDatabaseId,
+						  CStringGetDatum(subname));
+	if (!OidIsValid(oid) && !missing_ok)
+		ereport(ERROR,
+				(errcode(ERRCODE_UNDEFINED_OBJECT),
+				 errmsg("subscription \"%s\" does not exist", subname)));
+	return oid;
+}
+
+/*
+ * get_subscription_name - given a subscription OID, look up the name
+ */
+char *
+get_subscription_name(Oid subid)
+{
+	HeapTuple		tup;
+	char		   *subname;
+	Form_pg_subscription subform;
+
+	tup = SearchSysCache1(SUBSCRIPTIONOID, ObjectIdGetDatum(subid));
+
+	if (!HeapTupleIsValid(tup))
+		elog(ERROR, "cache lookup failed for subscription %u", subid);
+
+	subform = (Form_pg_subscription) GETSTRUCT(tup);
+	subname = pstrdup(NameStr(subform->subname));
+
+	ReleaseSysCache(tup);
+
+	return subname;
+}
+
+/*
+ * Convert text array to list of strings.
+ *
+ * Note: the resulting list of strings is pallocated here.
+ */
+static List *
+textarray_to_stringlist(ArrayType *textarray)
+{
+	Datum		   *elems;
+	int				nelems, i;
+	List		   *res = NIL;
+
+	deconstruct_array(textarray,
+					  TEXTOID, -1, false, 'i',
+					  &elems, NULL, &nelems);
+
+	if (nelems == 0)
+		return NIL;
+
+	for (i = 0; i < nelems; i++)
+		res = lappend(res, makeString(pstrdup(TextDatumGetCString(elems[i]))));
+
+	return res;
+}

src/backend/catalog/system_views.sql

@@ -248,6 +248,15 @@ CREATE VIEW pg_stats WITH (security_barrier) AS
 
 REVOKE ALL on pg_statistic FROM public;
 
+CREATE VIEW pg_publication_tables AS
+    SELECT
+        P.pubname AS pubname,
+        N.nspname AS schemaname,
+        C.relname AS tablename
+    FROM pg_publication P, pg_class C
+         JOIN pg_namespace N ON (N.oid = C.relnamespace)
+    WHERE C.oid IN (SELECT relid FROM pg_get_publication_tables(P.pubname));
+
 CREATE VIEW pg_locks AS
     SELECT * FROM pg_lock_status() AS L;
 
@@ -708,6 +717,20 @@ CREATE VIEW pg_stat_wal_receiver AS
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
 
+CREATE VIEW pg_stat_subscription AS
+    SELECT
+            su.oid AS subid,
+            su.subname,
+            st.pid,
+            st.received_lsn,
+            st.last_msg_send_time,
+            st.last_msg_receipt_time,
+            st.latest_end_lsn,
+            st.latest_end_time
+    FROM pg_subscription su
+            LEFT JOIN pg_stat_get_subscription(NULL) st
+                      ON (st.subid = su.oid);
+
 CREATE VIEW pg_stat_ssl AS
     SELECT
             S.pid,
@@ -866,6 +889,8 @@ CREATE VIEW pg_replication_origin_status AS
 
 REVOKE ALL ON pg_replication_origin_status FROM public;
 
+REVOKE ALL ON pg_subscription FROM public;
+
 --
 -- We have a few function definitions in here, too.
 -- At some point there might be enough to justify breaking them out into

src/backend/commands/Makefile

@@ -17,9 +17,9 @@ OBJS = amcmds.o aggregatecmds.o alter.o analyze.o async.o cluster.o comment.o \
 	dbcommands.o define.o discard.o dropcmds.o \
 	event_trigger.o explain.o extension.o foreigncmds.o functioncmds.o \
 	indexcmds.o lockcmds.o matview.o operatorcmds.o opclasscmds.o \
-	policy.o portalcmds.o prepare.o proclang.o \
-	schemacmds.o seclabel.o sequence.o tablecmds.o tablespace.o trigger.o \
-	tsearchcmds.o typecmds.o user.o vacuum.o vacuumlazy.o \
-	variable.o view.o
+	policy.o portalcmds.o prepare.o proclang.o publicationcmds.o \
+	schemacmds.o seclabel.o sequence.o subscriptioncmds.o tablecmds.o \
+	tablespace.o trigger.o tsearchcmds.o typecmds.o user.o vacuum.o \
+	vacuumlazy.o variable.o view.o
 
 include $(top_srcdir)/src/backend/common.mk

src/backend/commands/alter.c

@@ -45,7 +45,9 @@
 #include "commands/extension.h"
 #include "commands/policy.h"
 #include "commands/proclang.h"
+#include "commands/publicationcmds.h"
 #include "commands/schemacmds.h"
+#include "commands/subscriptioncmds.h"
 #include "commands/tablecmds.h"
 #include "commands/tablespace.h"
 #include "commands/trigger.h"
@@ -770,6 +772,14 @@ ExecAlterOwnerStmt(AlterOwnerStmt *stmt)
 			return AlterEventTriggerOwner(strVal(linitial(stmt->object)),
 										  newowner);
 
+		case OBJECT_PUBLICATION:
+			return AlterPublicationOwner(strVal(linitial(stmt->object)),
+										 newowner);
+
+		case OBJECT_SUBSCRIPTION:
+			return AlterSubscriptionOwner(strVal(linitial(stmt->object)),
+										  newowner);
+
 			/* Generic cases */
 		case OBJECT_AGGREGATE:
 		case OBJECT_COLLATION:

src/backend/commands/dbcommands.c

@@ -37,6 +37,7 @@
 #include "catalog/pg_authid.h"
 #include "catalog/pg_database.h"
 #include "catalog/pg_db_role_setting.h"
+#include "catalog/pg_subscription.h"
 #include "catalog/pg_tablespace.h"
 #include "commands/comment.h"
 #include "commands/dbcommands.h"
@@ -790,6 +791,7 @@ dropdb(const char *dbname, bool missing_ok)
 	int			npreparedxacts;
 	int			nslots,
 				nslots_active;
+	int			nsubscriptions;
 
 	/*
 	 * Look up the target database's OID, and get exclusive lock on it. We
@@ -874,6 +876,21 @@ dropdb(const char *dbname, bool missing_ok)
 						dbname),
 				 errdetail_busy_db(notherbackends, npreparedxacts)));
 
+	/*
+	 * Check if there are subscriptions defined in the target database.
+	 *
+	 * We can't drop them automatically because they might be holding
+	 * resources in other databases/instances.
+	 */
+	if ((nsubscriptions = CountDBSubscriptions(db_id)) > 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_IN_USE),
+				 errmsg("database \"%s\" is being used by logical replication subscription",
+						dbname),
+				 errdetail_plural("There is %d subscription.",
+								  "There are %d subscriptions.",
+								  nsubscriptions, nsubscriptions)));
+
 	/*
 	 * Remove the database's tuple from pg_database.
 	 */

src/backend/commands/define.c

@@ -319,3 +319,31 @@ defGetTypeLength(DefElem *def)
 					def->defname, defGetString(def))));
 	return 0;					/* keep compiler quiet */
 }
+
+/*
+ * Extract a list of string values (otherwise uninterpreted) from a DefElem.
+ */
+List *
+defGetStringList(DefElem *def)
+{
+	ListCell   *cell;
+
+	if (def->arg == NULL)
+		ereport(ERROR,
+				(errcode(ERRCODE_SYNTAX_ERROR),
+				 errmsg("%s requires a parameter",
+						def->defname)));
+	if (nodeTag(def->arg) != T_List)
+		elog(ERROR, "unrecognized node type: %d", (int) nodeTag(def->arg));
+
+	foreach(cell, (List *)def->arg)
+	{
+		Node	   *str = (Node *) lfirst(cell);
+
+		if (!IsA(str, String))
+			elog(ERROR, "unexpected node type in name list: %d",
+				 (int) nodeTag(str));
+	}
+
+	return (List *) def->arg;
+}

src/backend/commands/dropcmds.c

@@ -441,6 +441,10 @@ does_not_exist_skipping(ObjectType objtype, List *objname, List *objargs)
 				}
 			}
 			break;
+		case OBJECT_PUBLICATION:
+			msg = gettext_noop("publication \"%s\" does not exist, skipping");
+			name = NameListToString(objname);
+			break;
 		default:
 			elog(ERROR, "unrecognized object type: %d", (int) objtype);
 			break;

src/backend/commands/event_trigger.c

@@ -106,11 +106,13 @@ static event_trigger_support_data event_trigger_support[] = {
 	{"OPERATOR CLASS", true},
 	{"OPERATOR FAMILY", true},
 	{"POLICY", true},
+	{"PUBLICATION", true},
 	{"ROLE", false},
 	{"RULE", true},
 	{"SCHEMA", true},
 	{"SEQUENCE", true},
 	{"SERVER", true},
+	{"SUBSCRIPTION", true},
 	{"TABLE", true},
 	{"TABLESPACE", false},
 	{"TRANSFORM", true},
@@ -1103,9 +1105,12 @@ EventTriggerSupportsObjectType(ObjectType obtype)
 		case OBJECT_OPERATOR:
 		case OBJECT_OPFAMILY:
 		case OBJECT_POLICY:
+		case OBJECT_PUBLICATION:
+		case OBJECT_PUBLICATION_REL:
 		case OBJECT_RULE:
 		case OBJECT_SCHEMA:
 		case OBJECT_SEQUENCE:
+		case OBJECT_SUBSCRIPTION:
 		case OBJECT_TABCONSTRAINT:
 		case OBJECT_TABLE:
 		case OBJECT_TRANSFORM:
@@ -1168,6 +1173,9 @@ EventTriggerSupportsObjectClass(ObjectClass objclass)
 		case OCLASS_EXTENSION:
 		case OCLASS_POLICY:
 		case OCLASS_AM:
+		case OCLASS_PUBLICATION:
+		case OCLASS_PUBLICATION_REL:
+		case OCLASS_SUBSCRIPTION:
 			return true;
 	}
 

src/backend/commands/tablecmds.c

@@ -12055,6 +12055,18 @@ ATPrepChangePersistence(Relation rel, bool toLogged)
 			break;
 	}
 
+	/*
+	 * Check that the table is not part any publication when changing to
+	 * UNLOGGED as UNLOGGED tables can't be published.
+	 */
+	if (!toLogged &&
+		list_length(GetRelationPublications(RelationGetRelid(rel))) > 0)
+		ereport(ERROR,
+				(errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
+				 errmsg("cannot change table \"%s\" to unlogged because it is part of a publication",
+						RelationGetRelationName(rel)),
+				 errdetail("Unlogged relations cannot be replicated.")));
+
 	/*
 	 * Check existing foreign key constraints to preserve the invariant that
 	 * permanent tables cannot reference unlogged ones.  Self-referencing

src/backend/executor/Makefile

@@ -14,7 +14,7 @@ include $(top_builddir)/src/Makefile.global
 
 OBJS = execAmi.o execCurrent.o execGrouping.o execIndexing.o execJunk.o \
        execMain.o execParallel.o execProcnode.o execQual.o \
-       execScan.o execTuples.o \
+       execReplication.o execScan.o execTuples.o \
        execUtils.o functions.o instrument.o nodeAppend.o nodeAgg.o \
        nodeBitmapAnd.o nodeBitmapOr.o \
        nodeBitmapHeapscan.o nodeBitmapIndexscan.o \

src/backend/executor/execMain.c

@@ -43,6 +43,7 @@
 #include "access/xact.h"
 #include "catalog/namespace.h"
 #include "catalog/partition.h"
+#include "catalog/pg_publication.h"
 #include "commands/matview.h"
 #include "commands/trigger.h"
 #include "executor/execdebug.h"
@@ -1024,7 +1025,7 @@ CheckValidResultRel(Relation resultRel, CmdType operation)
 	{
 		case RELKIND_RELATION:
 		case RELKIND_PARTITIONED_TABLE:
-			/* OK */
+			CheckCmdReplicaIdentity(resultRel, operation);
 			break;
 		case RELKIND_SEQUENCE:
 			ereport(ERROR,

src/backend/nodes/copyfuncs.c

@@ -4286,6 +4286,69 @@ _copyPartitionCmd(const PartitionCmd *from)
 	return newnode;
 }
 
+static CreatePublicationStmt *
+_copyCreatePublicationStmt(const CreatePublicationStmt *from)
+{
+	CreatePublicationStmt *newnode = makeNode(CreatePublicationStmt);
+
+	COPY_STRING_FIELD(pubname);
+	COPY_NODE_FIELD(options);
+	COPY_NODE_FIELD(tables);
+	COPY_SCALAR_FIELD(for_all_tables);
+
+	return newnode;
+}
+
+static AlterPublicationStmt *
+_copyAlterPublicationStmt(const AlterPublicationStmt *from)
+{
+	AlterPublicationStmt *newnode = makeNode(AlterPublicationStmt);
+
+	COPY_STRING_FIELD(pubname);
+	COPY_NODE_FIELD(options);
+	COPY_NODE_FIELD(tables);
+	COPY_SCALAR_FIELD(for_all_tables);
+	COPY_SCALAR_FIELD(tableAction);
+
+	return newnode;
+}
+
+static CreateSubscriptionStmt *
+_copyCreateSubscriptionStmt(const CreateSubscriptionStmt *from)
+{
+	CreateSubscriptionStmt *newnode = makeNode(CreateSubscriptionStmt);
+
+	COPY_STRING_FIELD(subname);
+	COPY_STRING_FIELD(conninfo);
+	COPY_NODE_FIELD(publication);
+	COPY_NODE_FIELD(options);
+
+	return newnode;
+}
+
+static AlterSubscriptionStmt *
+_copyAlterSubscriptionStmt(const AlterSubscriptionStmt *from)
+{
+	AlterSubscriptionStmt *newnode = makeNode(AlterSubscriptionStmt);
+
+	COPY_STRING_FIELD(subname);
+	COPY_NODE_FIELD(options);
+
+	return newnode;
+}
+
+static DropSubscriptionStmt *
+_copyDropSubscriptionStmt(const DropSubscriptionStmt *from)
+{
+	DropSubscriptionStmt *newnode = makeNode(DropSubscriptionStmt);
+
+	COPY_STRING_FIELD(subname);
+	COPY_SCALAR_FIELD(drop_slot);
+	COPY_SCALAR_FIELD(missing_ok);
+
+	return newnode;
+}
+
 /* ****************************************************************
  *					pg_list.h copy functions
  * ****************************************************************
@@ -5086,6 +5149,21 @@ copyObject(const void *from)
 		case T_AlterPolicyStmt:
 			retval = _copyAlterPolicyStmt(from);
 			break;
+		case T_CreatePublicationStmt:
+			retval = _copyCreatePublicationStmt(from);
+			break;
+		case T_AlterPublicationStmt:
+			retval = _copyAlterPublicationStmt(from);
+			break;
+		case T_CreateSubscriptionStmt:
+			retval = _copyCreateSubscriptionStmt(from);
+			break;
+		case T_AlterSubscriptionStmt:
+			retval = _copyAlterSubscriptionStmt(from);
+			break;
+		case T_DropSubscriptionStmt:
+			retval = _copyDropSubscriptionStmt(from);
+			break;
 		case T_A_Expr:
 			retval = _copyAExpr(from);
 			break;

src/backend/postmaster/bgworker.c

@@ -20,6 +20,7 @@
 #include "port/atomics.h"
 #include "postmaster/bgworker_internals.h"
 #include "postmaster/postmaster.h"
+#include "replication/logicallauncher.h"
 #include "storage/dsm.h"
 #include "storage/ipc.h"
 #include "storage/latch.h"
@@ -107,6 +108,15 @@ struct BackgroundWorkerHandle
 
 static BackgroundWorkerArray *BackgroundWorkerData;
 
+/*
+ * List of workers that are allowed to be started outside of
+ * shared_preload_libraries.
+ */
+static const bgworker_main_type InternalBGWorkers[] = {
+	ApplyLauncherMain,
+	NULL
+};
+
 /*
  * Calculate shared memory needed.
  */
@@ -761,12 +771,23 @@ RegisterBackgroundWorker(BackgroundWorker *worker)
 {
 	RegisteredBgWorker *rw;
 	static int	numworkers = 0;
+	bool		internal = false;
+	int			i;
 
 	if (!IsUnderPostmaster)
 		ereport(DEBUG1,
 		 (errmsg("registering background worker \"%s\"", worker->bgw_name)));
 
-	if (!process_shared_preload_libraries_in_progress)
+	for (i = 0; InternalBGWorkers[i]; i++)
+	{
+		if (worker->bgw_main == InternalBGWorkers[i])
+		{
+			internal = true;
+			break;
+		}
+	}
+
+	if (!process_shared_preload_libraries_in_progress && !internal)
 	{
 		if (!IsUnderPostmaster)
 			ereport(LOG,

src/backend/postmaster/pgstat.c

@@ -3303,6 +3303,12 @@ pgstat_get_wait_activity(WaitEventActivity w)
 		case WAIT_EVENT_WAL_WRITER_MAIN:
 			event_name = "WalWriterMain";
 			break;
+		case WAIT_EVENT_LOGICAL_LAUNCHER_MAIN:
+			event_name = "LogicalLauncherMain";
+			break;
+		case WAIT_EVENT_LOGICAL_APPLY_MAIN:
+			event_name = "LogicalApplyMain";
+			break;
 		/* no default case, so that compiler will warn */
 	}
 

src/backend/postmaster/postmaster.c

@@ -113,6 +113,7 @@
 #include "postmaster/pgarch.h"
 #include "postmaster/postmaster.h"
 #include "postmaster/syslogger.h"
+#include "replication/logicallauncher.h"
 #include "replication/walsender.h"
 #include "storage/fd.h"
 #include "storage/ipc.h"
@@ -941,6 +942,14 @@ PostmasterMain(int argc, char *argv[])
 	}
 #endif
 
+	/*
+	 * Register the apply launcher.  Since it registers a background worker,
+	 * it needs to be called before InitializeMaxBackends(), and it's probably
+	 * a good idea to call it before any modules had chance to take the
+	 * background worker slots.
+	 */
+	ApplyLauncherRegister();
+
 	/*
 	 * process any libraries that should be preloaded at postmaster start
 	 */