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doc/src/sgml/ref/create_publication.sgml
PostgreSQL documentation
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<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 [ ONLY ] <replaceable class="parameter">table_name</replaceable> [ * ] [, ...]
      | FOR ALL TABLES ]
    [ WITH ( <replaceable class="parameter">publication_parameter</replaceable> [= <replaceable class="parameter">value</replaceable>] [, ... ] ) ]
</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.  If
      <literal>ONLY</literal> is specified before the table name, only
      that table is added to the publication.  If <literal>ONLY</literal> is not
      specified, the table and all its descendant tables (if any) are added.
      Optionally, <literal>*</literal> can be specified after the table name to
      explicitly indicate that descendant tables are included.
      This does not apply to a partitioned table, however.  The partitions of
      a partitioned table are always implicitly considered part of the
      publication, so they are never explicitly added to the publication.
     </para>

     <para>
      Only persistent base tables and partitioned tables can be part of a
      publication.  Temporary tables, unlogged tables, foreign tables,
      materialized views, and regular views cannot be part of a publication.
     </para>

     <para>
      When a partitioned table is added to a publication, all of its existing
      and future partitions are implicitly considered to be part of the
      publication.  So, even operations that are performed directly on a
      partition are also published via publications that its ancestors are
      part of.
     </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>WITH ( <replaceable class="parameter">publication_parameter</replaceable> [= <replaceable class="parameter">value</replaceable>] [, ... ] )</literal></term>
    <listitem>
     <para>
      This clause specifies optional parameters for a publication.  The
      following parameters are supported:

      <variablelist>
       <varlistentry>
        <term><literal>publish</literal> (<type>string</type>)</term>
        <listitem>
         <para>
          This parameter determines which DML operations will be published by
          the new publication to the subscribers.  The value is
          comma-separated list of operations.  The allowed operations are
          <literal>insert</literal>, <literal>update</literal>,
          <literal>delete</literal>, and <literal>truncate</literal>.
          The default is to publish all actions,
          and so the default value for this option is
          <literal>'insert, update, delete, truncate'</literal>.
         </para>
        </listitem>
       </varlistentry>

       <varlistentry>
        <term><literal>publish_via_partition_root</literal> (<type>boolean</type>)</term>
        <listitem>
         <para>
          This parameter determines whether changes in a partitioned table (or
          on its partitions) contained in the publication will be published
          using the identity and schema of the partitioned table rather than
          that of the individual partitions that are actually changed; the
          latter is the default.  Enabling this allows the changes to be
          replicated into a non-partitioned table or a partitioned table
          consisting of a different set of partitions.
         </para>

         <para>
          If this is enabled, <literal>TRUNCATE</literal> operations performed
          directly on partitions are not replicated.
         </para>
        </listitem>
       </varlistentry>
      </variablelist></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</literal> 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 ownership
   rights on the table.  The <command>FOR ALL TABLES</command> clause requires
   the invoking user to be a 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</literal> defined.  Otherwise those operations will be
   disallowed on those tables.
  </para>

  <para>
   For an <command>INSERT ... ON CONFLICT</command> command, the publication will
   publish the operation that results from the command.  Depending
   on 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>ATTACH</command>ing a table into a partition tree whose root is
   published using a publication with <literal>publish_via_partition_root</literal>
   set to <literal>true</literal> does not result in the table's existing contents
   being replicated.
  </para>

  <para>
   <command>COPY ... FROM</command> commands are published
   as <command>INSERT</command> operations.
  </para>

  <para>
   <acronym>DDL</acronym> operations are not published.
  </para>
 </refsect1>

 <refsect1>
  <title>Examples</title>

  <para>
   Create a publication that publishes all changes in two tables:
<programlisting>
CREATE PUBLICATION mypublication FOR TABLE users, departments;
</programlisting>
  </para>

  <para>
   Create a publication that publishes all changes in all tables:
<programlisting>
CREATE PUBLICATION alltables FOR ALL TABLES;
</programlisting>
  </para>

  <para>
   Create a publication that only publishes <command>INSERT</command>
   operations in one table:
<programlisting>
CREATE PUBLICATION insert_only FOR TABLE mydata
    WITH (publish = 'insert');
</programlisting></para>
 </refsect1>

 <refsect1>
  <title>Compatibility</title>

  <para>
   <command>CREATE PUBLICATION</command> is a <productname>PostgreSQL</productname>
   extension.
  </para>
 </refsect1>

 <refsect1>
  <title>See Also</title>

  <simplelist type="inline">
   <member><xref linkend="sql-alterpublication"/></member>
   <member><xref linkend="sql-droppublication"/></member>
   <member><xref linkend="sql-createsubscription"/></member>
   <member><xref linkend="sql-altersubscription"/></member>
  </simplelist>
 </refsect1>
</refentry>
