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1<?xml version="1.0" encoding="UTF-8" standalone="no"?>2<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>ALTER FUNCTION</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="sql-alterforeigntable.html" title="ALTER FOREIGN TABLE" /><link rel="next" href="sql-altergroup.html" title="ALTER GROUP" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">ALTER FUNCTION</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-alterforeigntable.html" title="ALTER FOREIGN TABLE">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><th width="60%" align="center">SQL Commands</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-altergroup.html" title="ALTER GROUP">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-ALTERFUNCTION"><div class="titlepage"></div><a id="id-1.9.3.14.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">ALTER FUNCTION</span></h2><p>ALTER FUNCTION — change the definition of a function</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">3ALTER FUNCTION <em class="replaceable"><code>name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ]4 <em class="replaceable"><code>action</code></em> [ ... ] [ RESTRICT ]5ALTER FUNCTION <em class="replaceable"><code>name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ]6 RENAME TO <em class="replaceable"><code>new_name</code></em>7ALTER FUNCTION <em class="replaceable"><code>name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ]8 OWNER TO { <em class="replaceable"><code>new_owner</code></em> | CURRENT_ROLE | CURRENT_USER | SESSION_USER }9ALTER FUNCTION <em class="replaceable"><code>name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ]10 SET SCHEMA <em class="replaceable"><code>new_schema</code></em>11ALTER FUNCTION <em class="replaceable"><code>name</code></em> [ ( [ [ <em class="replaceable"><code>argmode</code></em> ] [ <em class="replaceable"><code>argname</code></em> ] <em class="replaceable"><code>argtype</code></em> [, ...] ] ) ]12 [ NO ] DEPENDS ON EXTENSION <em class="replaceable"><code>extension_name</code></em>13 14<span class="phrase">where <em class="replaceable"><code>action</code></em> is one of:</span>15 16 CALLED ON NULL INPUT | RETURNS NULL ON NULL INPUT | STRICT17 IMMUTABLE | STABLE | VOLATILE18 [ NOT ] LEAKPROOF19 [ EXTERNAL ] SECURITY INVOKER | [ EXTERNAL ] SECURITY DEFINER20 PARALLEL { UNSAFE | RESTRICTED | SAFE }21 COST <em class="replaceable"><code>execution_cost</code></em>22 ROWS <em class="replaceable"><code>result_rows</code></em>23 SUPPORT <em class="replaceable"><code>support_function</code></em>24 SET <em class="replaceable"><code>configuration_parameter</code></em> { TO | = } { <em class="replaceable"><code>value</code></em> | DEFAULT }25 SET <em class="replaceable"><code>configuration_parameter</code></em> FROM CURRENT26 RESET <em class="replaceable"><code>configuration_parameter</code></em>27 RESET ALL28</pre></div><div class="refsect1" id="id-1.9.3.14.5"><h2>Description</h2><p>29 <code class="command">ALTER FUNCTION</code> changes the definition of a30 function.31 </p><p>32 You must own the function to use <code class="command">ALTER FUNCTION</code>.33 To change a function's schema, you must also have <code class="literal">CREATE</code>34 privilege on the new schema. To alter the owner, you must be able to35 <code class="literal">SET ROLE</code> to the new owning role, and that role must36 have <code class="literal">CREATE</code> privilege on37 the function's schema. (These restrictions enforce that altering the owner38 doesn't do anything you couldn't do by dropping and recreating the function.39 However, a superuser can alter ownership of any function anyway.)40 </p></div><div class="refsect1" id="id-1.9.3.14.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p>41 The name (optionally schema-qualified) of an existing function. If no42 argument list is specified, the name must be unique in its schema.43 </p></dd><dt><span class="term"><em class="replaceable"><code>argmode</code></em></span></dt><dd><p>44 The mode of an argument: <code class="literal">IN</code>, <code class="literal">OUT</code>,45 <code class="literal">INOUT</code>, or <code class="literal">VARIADIC</code>.46 If omitted, the default is <code class="literal">IN</code>.47 Note that <code class="command">ALTER FUNCTION</code> does not actually pay48 any attention to <code class="literal">OUT</code> arguments, since only the input49 arguments are needed to determine the function's identity.50 So it is sufficient to list the <code class="literal">IN</code>, <code class="literal">INOUT</code>,51 and <code class="literal">VARIADIC</code> arguments.52 </p></dd><dt><span class="term"><em class="replaceable"><code>argname</code></em></span></dt><dd><p>53 The name of an argument.54 Note that <code class="command">ALTER FUNCTION</code> does not actually pay55 any attention to argument names, since only the argument data56 types are needed to determine the function's identity.57 </p></dd><dt><span class="term"><em class="replaceable"><code>argtype</code></em></span></dt><dd><p>58 The data type(s) of the function's arguments (optionally59 schema-qualified), if any.60 </p></dd><dt><span class="term"><em class="replaceable"><code>new_name</code></em></span></dt><dd><p>61 The new name of the function.62 </p></dd><dt><span class="term"><em class="replaceable"><code>new_owner</code></em></span></dt><dd><p>63 The new owner of the function. Note that if the function is64 marked <code class="literal">SECURITY DEFINER</code>, it will subsequently65 execute as the new owner.66 </p></dd><dt><span class="term"><em class="replaceable"><code>new_schema</code></em></span></dt><dd><p>67 The new schema for the function.68 </p></dd><dt><span class="term"><code class="literal">DEPENDS ON EXTENSION <em class="replaceable"><code>extension_name</code></em></code><br /></span><span class="term"><code class="literal">NO DEPENDS ON EXTENSION <em class="replaceable"><code>extension_name</code></em></code></span></dt><dd><p>69 This form marks the function as dependent on the extension, or no longer70 dependent on that extension if <code class="literal">NO</code> is specified.71 A function that's marked as dependent on an extension is dropped when the72 extension is dropped, even if <code class="literal">CASCADE</code> is not specified.73 A function can depend upon multiple extensions, and will be dropped when74 any one of those extensions is dropped.75 </p></dd><dt><span class="term"><code class="literal">CALLED ON NULL INPUT</code><br /></span><span class="term"><code class="literal">RETURNS NULL ON NULL INPUT</code><br /></span><span class="term"><code class="literal">STRICT</code></span></dt><dd><p><code class="literal">CALLED ON NULL INPUT</code> changes the function so76 that it will be invoked when some or all of its arguments are77 null. <code class="literal">RETURNS NULL ON NULL INPUT</code> or78 <code class="literal">STRICT</code> changes the function so that it is not79 invoked if any of its arguments are null; instead, a null result80 is assumed automatically. See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a>81 for more information.82 </p></dd><dt><span class="term"><code class="literal">IMMUTABLE</code><br /></span><span class="term"><code class="literal">STABLE</code><br /></span><span class="term"><code class="literal">VOLATILE</code></span></dt><dd><p>83 Change the volatility of the function to the specified setting.84 See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for details.85 </p></dd><dt><span class="term"><code class="literal">[<span class="optional"> EXTERNAL </span>] SECURITY INVOKER</code><br /></span><span class="term"><code class="literal">[<span class="optional"> EXTERNAL </span>] SECURITY DEFINER</code></span></dt><dd><p>86 Change whether the function is a security definer or not. The87 key word <code class="literal">EXTERNAL</code> is ignored for SQL88 conformance. See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information about89 this capability.90 </p></dd><dt><span class="term"><code class="literal">PARALLEL</code></span></dt><dd><p>91 Change whether the function is deemed safe for parallelism.92 See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for details.93 </p></dd><dt><span class="term"><code class="literal">LEAKPROOF</code></span></dt><dd><p>94 Change whether the function is considered leakproof or not.95 See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information about96 this capability.97 </p></dd><dt><span class="term"><code class="literal">COST</code> <em class="replaceable"><code>execution_cost</code></em></span></dt><dd><p>98 Change the estimated execution cost of the function.99 See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information.100 </p></dd><dt><span class="term"><code class="literal">ROWS</code> <em class="replaceable"><code>result_rows</code></em></span></dt><dd><p>101 Change the estimated number of rows returned by a set-returning102 function. See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information.103 </p></dd><dt><span class="term"><code class="literal">SUPPORT</code> <em class="replaceable"><code>support_function</code></em></span></dt><dd><p>104 Set or change the planner support function to use for this function.105 See <a class="xref" href="xfunc-optimization.html" title="38.11. Function Optimization Information">Section 38.11</a> for details. You must be106 superuser to use this option.107 </p><p>108 This option cannot be used to remove the support function altogether,109 since it must name a new support function. Use <code class="command">CREATE OR110 REPLACE FUNCTION</code> if you need to do that.111 </p></dd><dt><span class="term"><em class="replaceable"><code>configuration_parameter</code></em><br /></span><span class="term"><em class="replaceable"><code>value</code></em></span></dt><dd><p>112 Add or change the assignment to be made to a configuration parameter113 when the function is called. If114 <em class="replaceable"><code>value</code></em> is <code class="literal">DEFAULT</code>115 or, equivalently, <code class="literal">RESET</code> is used, the function-local116 setting is removed, so that the function executes with the value117 present in its environment. Use <code class="literal">RESET118 ALL</code> to clear all function-local settings.119 <code class="literal">SET FROM CURRENT</code> saves the value of the parameter that120 is current when <code class="command">ALTER FUNCTION</code> is executed as the value121 to be applied when the function is entered.122 </p><p>123 See <a class="xref" href="sql-set.html" title="SET"><span class="refentrytitle">SET</span></a> and124 <a class="xref" href="runtime-config.html" title="Chapter 20. Server Configuration">Chapter 20</a>125 for more information about allowed parameter names and values.126 </p></dd><dt><span class="term"><code class="literal">RESTRICT</code></span></dt><dd><p>127 Ignored for conformance with the SQL standard.128 </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.14.7"><h2>Examples</h2><p>129 To rename the function <code class="literal">sqrt</code> for type130 <code class="type">integer</code> to <code class="literal">square_root</code>:131</p><pre class="programlisting">132ALTER FUNCTION sqrt(integer) RENAME TO square_root;133</pre><p>134 </p><p>135 To change the owner of the function <code class="literal">sqrt</code> for type136 <code class="type">integer</code> to <code class="literal">joe</code>:137</p><pre class="programlisting">138ALTER FUNCTION sqrt(integer) OWNER TO joe;139</pre><p>140 </p><p>141 To change the schema of the function <code class="literal">sqrt</code> for type142 <code class="type">integer</code> to <code class="literal">maths</code>:143</p><pre class="programlisting">144ALTER FUNCTION sqrt(integer) SET SCHEMA maths;145</pre><p>146 </p><p>147 To mark the function <code class="literal">sqrt</code> for type148 <code class="type">integer</code> as being dependent on the extension149 <code class="literal">mathlib</code>:150</p><pre class="programlisting">151ALTER FUNCTION sqrt(integer) DEPENDS ON EXTENSION mathlib;152</pre><p>153 </p><p>154 To adjust the search path that is automatically set for a function:155</p><pre class="programlisting">156ALTER FUNCTION check_password(text) SET search_path = admin, pg_temp;157</pre><p>158 </p><p>159 To disable automatic setting of <code class="varname">search_path</code> for a function:160</p><pre class="programlisting">161ALTER FUNCTION check_password(text) RESET search_path;162</pre><p>163 The function will now execute with whatever search path is used by its164 caller.165 </p></div><div class="refsect1" id="id-1.9.3.14.8"><h2>Compatibility</h2><p>166 This statement is partially compatible with the <code class="command">ALTER167 FUNCTION</code> statement in the SQL standard. The standard allows more168 properties of a function to be modified, but does not provide the169 ability to rename a function, make a function a security definer,170 attach configuration parameter values to a function,171 or change the owner, schema, or volatility of a function. The standard also172 requires the <code class="literal">RESTRICT</code> key word, which is optional in173 <span class="productname">PostgreSQL</span>.174 </p></div><div class="refsect1" id="id-1.9.3.14.9"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a>, <a class="xref" href="sql-dropfunction.html" title="DROP FUNCTION"><span class="refentrytitle">DROP FUNCTION</span></a>, <a class="xref" href="sql-alterprocedure.html" title="ALTER PROCEDURE"><span class="refentrytitle">ALTER PROCEDURE</span></a>, <a class="xref" href="sql-alterroutine.html" title="ALTER ROUTINE"><span class="refentrytitle">ALTER ROUTINE</span></a></span></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="sql-alterforeigntable.html" title="ALTER FOREIGN TABLE">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="sql-commands.html" title="SQL Commands">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="sql-altergroup.html" title="ALTER GROUP">Next</a></td></tr><tr><td width="40%" align="left" valign="top">ALTER FOREIGN TABLE </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="40%" align="right" valign="top"> ALTER GROUP</td></tr></table></div></body></html>