<!--
doc/src/sgml/ref/alter_procedure.sgml
PostgreSQL documentation
-->

<refentry id="sql-alterprocedure">
 <indexterm zone="sql-alterprocedure">
  <primary>ALTER PROCEDURE</primary>
 </indexterm>

 <refmeta>
  <refentrytitle>ALTER PROCEDURE</refentrytitle>
  <manvolnum>7</manvolnum>
  <refmiscinfo>SQL - Language Statements</refmiscinfo>
 </refmeta>

 <refnamediv>
  <refname>ALTER PROCEDURE</refname>
  <refpurpose>change the definition of a procedure</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
<synopsis>
ALTER PROCEDURE <replaceable>name</replaceable> [ ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] ) ]
    <replaceable class="parameter">action</replaceable> [ ... ] [ RESTRICT ]
ALTER PROCEDURE <replaceable>name</replaceable> [ ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] ) ]
    RENAME TO <replaceable>new_name</replaceable>
ALTER PROCEDURE <replaceable>name</replaceable> [ ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] ) ]
    OWNER TO { <replaceable>new_owner</replaceable> | CURRENT_USER | SESSION_USER }
ALTER PROCEDURE <replaceable>name</replaceable> [ ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] ) ]
    SET SCHEMA <replaceable>new_schema</replaceable>
ALTER PROCEDURE <replaceable>name</replaceable> [ ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] ) ]
    DEPENDS ON EXTENSION <replaceable>extension_name</replaceable>

<phrase>where <replaceable class="parameter">action</replaceable> is one of:</phrase>

    [ EXTERNAL ] SECURITY INVOKER | [ EXTERNAL ] SECURITY DEFINER
    SET <replaceable class="parameter">configuration_parameter</replaceable> { TO | = } { <replaceable class="parameter">value</replaceable> | DEFAULT }
    SET <replaceable class="parameter">configuration_parameter</replaceable> FROM CURRENT
    RESET <replaceable class="parameter">configuration_parameter</replaceable>
    RESET ALL
</synopsis>
 </refsynopsisdiv>

 <refsect1>
  <title>Description</title>

  <para>
   <command>ALTER PROCEDURE</command> changes the definition of a
   procedure.
  </para>

  <para>
   You must own the procedure to use <command>ALTER PROCEDURE</command>.
   To change a procedure's schema, you must also have <literal>CREATE</literal>
   privilege on the new schema.
   To alter the owner, you must also be a direct or indirect member of the new
   owning role, and that role must have <literal>CREATE</literal> privilege on
   the procedure's schema.  (These restrictions enforce that altering the owner
   doesn't do anything you couldn't do by dropping and recreating the procedure.
   However, a superuser can alter ownership of any procedure anyway.)
  </para>
 </refsect1>

 <refsect1>
  <title>Parameters</title>

  <variablelist>
   <varlistentry>
    <term><replaceable class="parameter">name</replaceable></term>
    <listitem>
     <para>
      The name (optionally schema-qualified) of an existing procedure.  If no
      argument list is specified, the name must be unique in its schema.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">argmode</replaceable></term>

    <listitem>
     <para>
      The mode of an argument: <literal>IN</literal>  or <literal>VARIADIC</literal>.
      If omitted, the default is <literal>IN</literal>.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">argname</replaceable></term>

    <listitem>
     <para>
      The name of an argument.
      Note that <command>ALTER PROCEDURE</command> does not actually pay
      any attention to argument names, since only the argument data
      types are needed to determine the procedure's identity.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">argtype</replaceable></term>

    <listitem>
     <para>
      The data type(s) of the procedure's arguments (optionally
      schema-qualified), if any.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">new_name</replaceable></term>
    <listitem>
     <para>
      The new name of the procedure.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">new_owner</replaceable></term>
    <listitem>
     <para>
      The new owner of the procedure.  Note that if the procedure is
      marked <literal>SECURITY DEFINER</literal>, it will subsequently
      execute as the new owner.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">new_schema</replaceable></term>
    <listitem>
     <para>
      The new schema for the procedure.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><replaceable class="parameter">extension_name</replaceable></term>
    <listitem>
     <para>
      The name of the extension that the procedure is to depend on.
     </para>
    </listitem>
   </varlistentry>

   <varlistentry>
    <term><literal><optional> EXTERNAL </optional> SECURITY INVOKER</literal></term>
    <term><literal><optional> EXTERNAL </optional> SECURITY DEFINER</literal></term>

    <listitem>
     <para>
      Change whether the procedure is a security definer or not. The
      key word <literal>EXTERNAL</literal> is ignored for SQL
      conformance. See <xref linkend="sql-createprocedure"/> for more information about
      this capability.
     </para>
    </listitem>
   </varlistentry>

     <varlistentry>
      <term><replaceable>configuration_parameter</replaceable></term>
      <term><replaceable>value</replaceable></term>
      <listitem>
       <para>
        Add or change the assignment to be made to a configuration parameter
        when the procedure is called.  If
        <replaceable>value</replaceable> is <literal>DEFAULT</literal>
        or, equivalently, <literal>RESET</literal> is used, the procedure-local
        setting is removed, so that the procedure executes with the value
        present in its environment.  Use <literal>RESET
        ALL</literal> to clear all procedure-local settings.
        <literal>SET FROM CURRENT</literal> saves the value of the parameter that
        is current when <command>ALTER PROCEDURE</command> is executed as the value
        to be applied when the procedure is entered.
       </para>

       <para>
        See <xref linkend="sql-set"/> and
        <xref linkend="runtime-config"/>
        for more information about allowed parameter names and values.
       </para>
      </listitem>
     </varlistentry>

   <varlistentry>
    <term><literal>RESTRICT</literal></term>

    <listitem>
     <para>
      Ignored for conformance with the SQL standard.
     </para>
    </listitem>
   </varlistentry>
  </variablelist>
 </refsect1>

 <refsect1>
  <title>Examples</title>

  <para>
   To rename the procedure <literal>insert_data</literal> with two arguments
   of type <type>integer</type> to <literal>insert_record</literal>:
<programlisting>
ALTER PROCEDURE insert_data(integer, integer) RENAME TO insert_record;
</programlisting>
  </para>

  <para>
   To change the owner of the procedure <literal>insert_data</literal> with
   two arguments of type <type>integer</type> to <literal>joe</literal>:
<programlisting>
ALTER PROCEDURE insert_data(integer, integer) OWNER TO joe;
</programlisting>
  </para>

  <para>
   To change the schema of the procedure <literal>insert_data</literal> with
   two arguments of type <type>integer</type>
   to <literal>accounting</literal>:
<programlisting>
ALTER PROCEDURE insert_data(integer, integer) SET SCHEMA accounting;
</programlisting>
  </para>

  <para>
   To mark the procedure <literal>insert_data(integer, integer)</literal> as
   being dependent on the extension <literal>myext</literal>:
<programlisting>
ALTER PROCEDURE insert_data(integer, integer) DEPENDS ON EXTENSION myext;
</programlisting>
  </para>

  <para>
   To adjust the search path that is automatically set for a procedure:
<programlisting>
ALTER PROCEDURE check_password(text) SET search_path = admin, pg_temp;
</programlisting>
  </para>

  <para>
   To disable automatic setting of <varname>search_path</varname> for a procedure:
<programlisting>
ALTER PROCEDURE check_password(text) RESET search_path;
</programlisting>
   The procedure will now execute with whatever search path is used by its
   caller.
  </para>
 </refsect1>

 <refsect1>
  <title>Compatibility</title>

  <para>
   This statement is partially compatible with the <command>ALTER
   PROCEDURE</command> statement in the SQL standard. The standard allows more
   properties of a procedure to be modified, but does not provide the
   ability to rename a procedure, make a procedure a security definer,
   attach configuration parameter values to a procedure,
   or change the owner, schema, or volatility of a procedure. The standard also
   requires the <literal>RESTRICT</literal> key word, which is optional in
   <productname>PostgreSQL</productname>.
  </para>
 </refsect1>

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

  <simplelist type="inline">
   <member><xref linkend="sql-createprocedure"/></member>
   <member><xref linkend="sql-dropprocedure"/></member>
   <member><xref linkend="sql-alterfunction"/></member>
   <member><xref linkend="sql-alterroutine"/></member>
  </simplelist>
 </refsect1>
</refentry>
