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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>CALL</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-begin.html" title="BEGIN" /><link rel="next" href="sql-checkpoint.html" title="CHECKPOINT" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">CALL</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="sql-begin.html" title="BEGIN">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 18.0 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="sql-checkpoint.html" title="CHECKPOINT">Next</a></td></tr></table><hr /></div><div class="refentry" id="SQL-CALL"><div class="titlepage"></div><a id="id-1.9.3.48.1" class="indexterm"></a><div class="refnamediv"><h2><span class="refentrytitle">CALL</span></h2><p>CALL — invoke a procedure</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">
   3 CALL <em class="replaceable"><code>name</code></em> ( [ <em class="replaceable"><code>argument</code></em> ] [, ...] )
   4 </pre></div><div class="refsect1" id="id-1.9.3.48.5"><h2>Description</h2><p>
   5    <code class="command">CALL</code> executes a procedure.
   6   </p><p>
   7    If the procedure has any output parameters, then a result row will be
   8    returned, containing the values of those parameters.
   9   </p></div><div class="refsect1" id="id-1.9.3.48.6"><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="replaceable"><code>name</code></em></span></dt><dd><p>
  10       The name (optionally schema-qualified) of the procedure.
  11      </p></dd><dt><span class="term"><em class="replaceable"><code>argument</code></em></span></dt><dd><p>
  12       An argument expression for the procedure call.
  13      </p><p>
  14       Arguments can include parameter names, using the syntax
  15       <code class="literal"><em class="replaceable"><code>name</code></em> =&gt; <em class="replaceable"><code>value</code></em></code>.
  16       This works the same as in ordinary function calls; see
  17       <a class="xref" href="sql-syntax-calling-funcs.html" title="4.3. Calling Functions">Section 4.3</a> for details.
  18      </p><p>
  19       Arguments must be supplied for all procedure parameters that lack
  20       defaults, including <code class="literal">OUT</code> parameters.  However,
  21       arguments matching <code class="literal">OUT</code> parameters are not evaluated,
  22       so it's customary to just write <code class="literal">NULL</code> for them.
  23       (Writing something else for an <code class="literal">OUT</code> parameter
  24       might cause compatibility problems with
  25       future <span class="productname">PostgreSQL</span> versions.)
  26      </p></dd></dl></div></div><div class="refsect1" id="id-1.9.3.48.7"><h2>Notes</h2><p>
  27    The user must have <code class="literal">EXECUTE</code> privilege on the procedure in
  28    order to be allowed to invoke it.
  29   </p><p>
  30    To call a function (not a procedure), use <code class="command">SELECT</code> instead.
  31   </p><p>
  32    If <code class="command">CALL</code> is executed in a transaction block, then the
  33    called procedure cannot execute transaction control statements.
  34    Transaction control statements are only allowed if <code class="command">CALL</code>
  35    is executed in its own transaction.
  36   </p><p>
  37    <span class="application">PL/pgSQL</span> handles output parameters
  38    in <code class="command">CALL</code> commands differently;
  39    see <a class="xref" href="plpgsql-control-structures.html#PLPGSQL-STATEMENTS-CALLING-PROCEDURE" title="41.6.3. Calling a Procedure">Section 41.6.3</a>.
  40   </p></div><div class="refsect1" id="id-1.9.3.48.8"><h2>Examples</h2><pre class="programlisting">
  41 CALL do_db_maintenance();
  42 </pre></div><div class="refsect1" id="id-1.9.3.48.9"><h2>Compatibility</h2><p>
  43    <code class="command">CALL</code> conforms to the SQL standard,
  44    except for the handling of output parameters.  The standard
  45    says that users should write variables to receive the values
  46    of output parameters.
  47   </p></div><div class="refsect1" id="id-1.9.3.48.10"><h2>See Also</h2><span class="simplelist"><a class="xref" href="sql-createprocedure.html" title="CREATE PROCEDURE"><span class="refentrytitle">CREATE PROCEDURE</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-begin.html" title="BEGIN">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-checkpoint.html" title="CHECKPOINT">Next</a></td></tr><tr><td width="40%" align="left" valign="top">BEGIN </td><td width="20%" align="center"><a accesskey="h" href="index.html" title="PostgreSQL 18.0 Documentation">Home</a></td><td width="40%" align="right" valign="top"> CHECKPOINT</td></tr></table></div></body></html>