1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
|
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!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 15.7 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">
ALTER 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> [, ...] ] ) ]
<em class="replaceable"><code>action</code></em> [ ... ] [ RESTRICT ]
ALTER 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> [, ...] ] ) ]
RENAME TO <em class="replaceable"><code>new_name</code></em>
ALTER 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> [, ...] ] ) ]
OWNER TO { <em class="replaceable"><code>new_owner</code></em> | CURRENT_ROLE | CURRENT_USER | SESSION_USER }
ALTER 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> [, ...] ] ) ]
SET SCHEMA <em class="replaceable"><code>new_schema</code></em>
ALTER 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> [, ...] ] ) ]
[ NO ] DEPENDS ON EXTENSION <em class="replaceable"><code>extension_name</code></em>
<span class="phrase">where <em class="replaceable"><code>action</code></em> is one of:</span>
CALLED ON NULL INPUT | RETURNS NULL ON NULL INPUT | STRICT
IMMUTABLE | STABLE | VOLATILE
[ NOT ] LEAKPROOF
[ EXTERNAL ] SECURITY INVOKER | [ EXTERNAL ] SECURITY DEFINER
PARALLEL { UNSAFE | RESTRICTED | SAFE }
COST <em class="replaceable"><code>execution_cost</code></em>
ROWS <em class="replaceable"><code>result_rows</code></em>
SUPPORT <em class="replaceable"><code>support_function</code></em>
SET <em class="replaceable"><code>configuration_parameter</code></em> { TO | = } { <em class="replaceable"><code>value</code></em> | DEFAULT }
SET <em class="replaceable"><code>configuration_parameter</code></em> FROM CURRENT
RESET <em class="replaceable"><code>configuration_parameter</code></em>
RESET ALL
</pre></div><div class="refsect1" id="id-1.9.3.14.5"><h2>Description</h2><p>
<code class="command">ALTER FUNCTION</code> changes the definition of a
function.
</p><p>
You must own the function to use <code class="command">ALTER FUNCTION</code>.
To change a function's schema, you must also have <code class="literal">CREATE</code>
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 <code class="literal">CREATE</code> privilege on
the function's schema. (These restrictions enforce that altering the owner
doesn't do anything you couldn't do by dropping and recreating the function.
However, a superuser can alter ownership of any function anyway.)
</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>
The name (optionally schema-qualified) of an existing function. If no
argument list is specified, the name must be unique in its schema.
</p></dd><dt><span class="term"><em class="replaceable"><code>argmode</code></em></span></dt><dd><p>
The mode of an argument: <code class="literal">IN</code>, <code class="literal">OUT</code>,
<code class="literal">INOUT</code>, or <code class="literal">VARIADIC</code>.
If omitted, the default is <code class="literal">IN</code>.
Note that <code class="command">ALTER FUNCTION</code> does not actually pay
any attention to <code class="literal">OUT</code> arguments, since only the input
arguments are needed to determine the function's identity.
So it is sufficient to list the <code class="literal">IN</code>, <code class="literal">INOUT</code>,
and <code class="literal">VARIADIC</code> arguments.
</p></dd><dt><span class="term"><em class="replaceable"><code>argname</code></em></span></dt><dd><p>
The name of an argument.
Note that <code class="command">ALTER FUNCTION</code> does not actually pay
any attention to argument names, since only the argument data
types are needed to determine the function's identity.
</p></dd><dt><span class="term"><em class="replaceable"><code>argtype</code></em></span></dt><dd><p>
The data type(s) of the function's arguments (optionally
schema-qualified), if any.
</p></dd><dt><span class="term"><em class="replaceable"><code>new_name</code></em></span></dt><dd><p>
The new name of the function.
</p></dd><dt><span class="term"><em class="replaceable"><code>new_owner</code></em></span></dt><dd><p>
The new owner of the function. Note that if the function is
marked <code class="literal">SECURITY DEFINER</code>, it will subsequently
execute as the new owner.
</p></dd><dt><span class="term"><em class="replaceable"><code>new_schema</code></em></span></dt><dd><p>
The new schema for the function.
</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>
This form marks the function as dependent on the extension, or no longer
dependent on that extension if <code class="literal">NO</code> is specified.
A function that's marked as dependent on an extension is dropped when the
extension is dropped, even if <code class="literal">CASCADE</code> is not specified.
A function can depend upon multiple extensions, and will be dropped when
any one of those extensions is dropped.
</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 so
that it will be invoked when some or all of its arguments are
null. <code class="literal">RETURNS NULL ON NULL INPUT</code> or
<code class="literal">STRICT</code> changes the function so that it is not
invoked if any of its arguments are null; instead, a null result
is assumed automatically. See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a>
for more information.
</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>
Change the volatility of the function to the specified setting.
See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for details.
</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>
Change whether the function is a security definer or not. The
key word <code class="literal">EXTERNAL</code> is ignored for SQL
conformance. See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information about
this capability.
</p></dd><dt><span class="term"><code class="literal">PARALLEL</code></span></dt><dd><p>
Change whether the function is deemed safe for parallelism.
See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for details.
</p></dd><dt><span class="term"><code class="literal">LEAKPROOF</code></span></dt><dd><p>
Change whether the function is considered leakproof or not.
See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information about
this capability.
</p></dd><dt><span class="term"><code class="literal">COST</code> <em class="replaceable"><code>execution_cost</code></em></span></dt><dd><p>
Change the estimated execution cost of the function.
See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information.
</p></dd><dt><span class="term"><code class="literal">ROWS</code> <em class="replaceable"><code>result_rows</code></em></span></dt><dd><p>
Change the estimated number of rows returned by a set-returning
function. See <a class="xref" href="sql-createfunction.html" title="CREATE FUNCTION"><span class="refentrytitle">CREATE FUNCTION</span></a> for more information.
</p></dd><dt><span class="term"><code class="literal">SUPPORT</code> <em class="replaceable"><code>support_function</code></em></span></dt><dd><p>
Set or change the planner support function to use for this function.
See <a class="xref" href="xfunc-optimization.html" title="38.11. Function Optimization Information">Section 38.11</a> for details. You must be
superuser to use this option.
</p><p>
This option cannot be used to remove the support function altogether,
since it must name a new support function. Use <code class="command">CREATE OR
REPLACE FUNCTION</code> if you need to do that.
</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>
Add or change the assignment to be made to a configuration parameter
when the function is called. If
<em class="replaceable"><code>value</code></em> is <code class="literal">DEFAULT</code>
or, equivalently, <code class="literal">RESET</code> is used, the function-local
setting is removed, so that the function executes with the value
present in its environment. Use <code class="literal">RESET
ALL</code> to clear all function-local settings.
<code class="literal">SET FROM CURRENT</code> saves the value of the parameter that
is current when <code class="command">ALTER FUNCTION</code> is executed as the value
to be applied when the function is entered.
</p><p>
See <a class="xref" href="sql-set.html" title="SET"><span class="refentrytitle">SET</span></a> and
<a class="xref" href="runtime-config.html" title="Chapter 20. Server Configuration">Chapter 20</a>
for more information about allowed parameter names and values.
</p></dd><dt><span class="term"><code class="literal">RESTRICT</code></span></dt><dd><p>
Ignored for conformance with the SQL standard.
</p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.14.7"><h2>Examples</h2><p>
To rename the function <code class="literal">sqrt</code> for type
<code class="type">integer</code> to <code class="literal">square_root</code>:
</p><pre class="programlisting">
ALTER FUNCTION sqrt(integer) RENAME TO square_root;
</pre><p>
</p><p>
To change the owner of the function <code class="literal">sqrt</code> for type
<code class="type">integer</code> to <code class="literal">joe</code>:
</p><pre class="programlisting">
ALTER FUNCTION sqrt(integer) OWNER TO joe;
</pre><p>
</p><p>
To change the schema of the function <code class="literal">sqrt</code> for type
<code class="type">integer</code> to <code class="literal">maths</code>:
</p><pre class="programlisting">
ALTER FUNCTION sqrt(integer) SET SCHEMA maths;
</pre><p>
</p><p>
To mark the function <code class="literal">sqrt</code> for type
<code class="type">integer</code> as being dependent on the extension
<code class="literal">mathlib</code>:
</p><pre class="programlisting">
ALTER FUNCTION sqrt(integer) DEPENDS ON EXTENSION mathlib;
</pre><p>
</p><p>
To adjust the search path that is automatically set for a function:
</p><pre class="programlisting">
ALTER FUNCTION check_password(text) SET search_path = admin, pg_temp;
</pre><p>
</p><p>
To disable automatic setting of <code class="varname">search_path</code> for a function:
</p><pre class="programlisting">
ALTER FUNCTION check_password(text) RESET search_path;
</pre><p>
The function will now execute with whatever search path is used by its
caller.
</p></div><div class="refsect1" id="id-1.9.3.14.8"><h2>Compatibility</h2><p>
This statement is partially compatible with the <code class="command">ALTER
FUNCTION</code> statement in the SQL standard. The standard allows more
properties of a function to be modified, but does not provide the
ability to rename a function, make a function a security definer,
attach configuration parameter values to a function,
or change the owner, schema, or volatility of a function. The standard also
requires the <code class="literal">RESTRICT</code> key word, which is optional in
<span class="productname">PostgreSQL</span>.
</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 15.7 Documentation">Home</a></td><td width="40%" align="right" valign="top"> ALTER GROUP</td></tr></table></div></body></html>
|
