<literal>OUTPUT_PLUGIN_TEXTUAL_OUTPUT</literal>
      or <literal>OUTPUT_PLUGIN_BINARY_OUTPUT</literal>. See also
      <xref linkend="logicaldecoding-output-mode"/>.
      If <literal>receive_rewrites</literal> is true, the output plugin will
      also be called for changes made by heap rewrites during certain DDL
      operations.  These are of interest to plugins that handle DDL
      replication, but they require special handling.
     </para>

     <para>
      The startup callback should validate the options present in
      <literal>ctx-&gt;output_plugin_options</literal>. If the output plugin
      needs to have a state, it can
      use <literal>ctx-&gt;output_plugin_private</literal> to store it.
     </para>
    </sect3>

    <sect3 id="logicaldecoding-output-plugin-shutdown">
     <title>Shutdown Callback</title>

     <para>
      The optional <function>shutdown_cb</function> callback is called
      whenever a formerly active replication slot is not used anymore and can
      be used to deallocate resources private to the output plugin. The slot
      isn't necessarily being dropped, streaming is just being stopped.
<programlisting>
typedef void (*LogicalDecodeShutdownCB) (struct LogicalDecodingContext *ctx);
</programlisting>
     </para>
    </sect3>

    <sect3 id="logicaldecoding-output-plugin-begin">
     <title>Transaction Begin Callback</title>

     <para>
      The required <function>begin_cb</function> callback is called whenever a
      start of a committed transaction has been decoded. Aborted transactions
      and their contents never get decoded.
<programlisting>
typedef void (*LogicalDecodeBeginCB) (struct LogicalDecodingContext *ctx,
                                      ReorderBufferTXN *txn);
</programlisting>
      The <parameter>txn</parameter> parameter contains meta information about
      the transaction, like the time stamp at which it has been committed and
      its XID.
     </para>
    </sect3>

    <sect3 id="logicaldecoding-output-plugin-commit">
     <title>Transaction End Callback</title>

     <para>
      The required <function>commit_cb</function> callback is called whenever
      a transaction commit has been
      decoded. The <function>change_cb</function> callbacks for all modified
      rows will have been called before this, if there have been any modified
      rows.
<programlisting>
typedef void (*LogicalDecodeCommitCB) (struct LogicalDecodingContext *ctx,
                                       ReorderBufferTXN *txn,
                                       XLogRecPtr commit_lsn);
</programlisting>
     </para>
    </sect3>

    <sect3 id="logicaldecoding-output-plugin-change">
     <title>Change Callback</title>

     <para>
      The required <function>change_cb</function> callback is called for every
      individual row modification inside a transaction, may it be
      an <command>INSERT</command>, <command>UPDATE</command>,
      or <command>DELETE</command>. Even if the original command modified
      several rows at once the callback will be called individually for each
      row. The <function>change_cb</function> callback may access system or
      user catalog tables to aid in the process of outputting the row
      modification details. In case of decoding a prepared (but yet
      uncommitted) transaction or decoding of an uncommitted transaction, this
      change callback might also error out due to simultaneous rollback of
      this very same transaction. In that case, the logical decoding of this
      aborted transaction is stopped gracefully.
<programlisting>
typedef void (*LogicalDecodeChangeCB) (struct LogicalDecodingContext *ctx,
                                       ReorderBufferTXN *txn,
                                       Relation relation,
                                       ReorderBufferChange *change);
</programlisting>
      The <parameter>ctx</parameter> and <parameter>txn</parameter> parameters
      have the same contents as for the