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$PostgreSQL: pgsql/doc/src/sgml/ref/create_function.sgml,v 1.56 2004/05/16 23:22:07 neilc Exp $

$PostgreSQL: pgsql/doc/src/sgml/ref/create_function.sgml,v 1.57 2004/06/25 07:05:34 dennis Exp $

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<refentry id="SQL-CREATEFUNCTION">

<refsynopsisdiv>

<synopsis>

CREATE [ OR REPLACE ] FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceable class="parameter">argtype</replaceable> [, ...] ] )

CREATE [ OR REPLACE ] FUNCTION <replaceable class="parameter">name</replaceable> ( [[ <replaceable class="parameter">argname</replaceable> ]<replaceable class="parameter">argtype</replaceable> [, ...] ] )

RETURNS <replaceable class="parameter">rettype</replaceable>

{ LANGUAGE <replaceable class="parameter">langname</replaceable>

| IMMUTABLE | STABLE | VOLATILE

| CALLED ON NULL INPUT | RETURNS NULL ON NULL INPUT | STRICT

| [EXTERNAL] SECURITY INVOKER | [EXTERNAL] SECURITY DEFINER

| [EXTERNAL] SECURITY INVOKER | [EXTERNAL] SECURITY DEFINER

| AS '<replaceable class="parameter">definition</replaceable>'

| AS '<replaceable class="parameter">obj_file</replaceable>', '<replaceable class="parameter">link_symbol</replaceable>'

} ...

</listitem>

</varlistentry>

<varlistentry>

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

<listitem>

<para>

The name of an argument. Some languages (currently only PL/pgSQL) let

you use the name in the function body. For other languages the

argument name is just extra documentation.

</para>

</listitem>

</varlistentry>

<varlistentry>

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