postgresql/doc/src/sgml/ref/drop_routine.sgml

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<!--
doc/src/sgml/ref/drop_routine.sgml
PostgreSQL documentation
-->
<refentry id="sql-droproutine">
<indexterm zone="sql-droproutine">
<primary>DROP ROUTINE</primary>
</indexterm>
<refmeta>
<refentrytitle>DROP ROUTINE</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>DROP ROUTINE</refname>
<refpurpose>remove a routine</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
DROP ROUTINE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> [ ( [ [ <replaceable class="parameter">argmode</replaceable> ] [ <replaceable class="parameter">argname</replaceable> ] <replaceable class="parameter">argtype</replaceable> [, ...] ] ) ] [, ...]
[ CASCADE | RESTRICT ]
</synopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
<command>DROP ROUTINE</command> removes the definition of one or more
existing routines. The term <quote>routine</quote> includes
aggregate functions, normal functions, and procedures. See
under <xref linkend="sql-dropaggregate"/>, <xref linkend="sql-dropfunction"/>,
and <xref linkend="sql-dropprocedure"/> for the description of the
parameters, more examples, and further details.
</para>
</refsect1>
<refsect1 id="sql-droproutine-notes">
<title>Notes</title>
<para>
The lookup rules used by <command>DROP ROUTINE</command> are
fundamentally the same as for <command>DROP PROCEDURE</command>; in
particular, <command>DROP ROUTINE</command> shares that command's
behavior of considering an argument list that has
no <replaceable class="parameter">argmode</replaceable> markers to be
possibly using the SQL standard's definition that <literal>OUT</literal>
arguments are included in the list. (<command>DROP AGGREGATE</command>
and <command>DROP FUNCTION</command> do not do that.)
</para>
<para>
In some cases where the same name is shared by routines of different
kinds, it is possible for <command>DROP ROUTINE</command> to fail with
an ambiguity error when a more specific command (<command>DROP
FUNCTION</command>, etc.) would work. Specifying the argument type
list more carefully will also resolve such problems.
</para>
<para>
These lookup rules are also used by other commands that
act on existing routines, such as <command>ALTER ROUTINE</command>
and <command>COMMENT ON ROUTINE</command>.
</para>
</refsect1>
<refsect1 id="sql-droproutine-examples">
<title>Examples</title>
<para>
To drop the routine <literal>foo</literal> for type
<type>integer</type>:
<programlisting>
DROP ROUTINE foo(integer);
</programlisting>
This command will work independent of whether <literal>foo</literal> is an
aggregate, function, or procedure.
</para>
</refsect1>
<refsect1 id="sql-droproutine-compatibility">
<title>Compatibility</title>
<para>
This command conforms to the SQL standard, with
these <productname>PostgreSQL</productname> extensions:
<itemizedlist>
<listitem>
<para>The standard only allows one routine to be dropped per command.</para>
</listitem>
<listitem>
<para>The <literal>IF EXISTS</literal> option is an extension.</para>
</listitem>
<listitem>
<para>The ability to specify argument modes and names is an
extension, and the lookup rules differ when modes are given.</para>
</listitem>
<listitem>
<para>User-definable aggregate functions are an extension.</para>
</listitem>
</itemizedlist></para>
</refsect1>
<refsect1>
<title>See Also</title>
<simplelist type="inline">
<member><xref linkend="sql-dropaggregate"/></member>
<member><xref linkend="sql-dropfunction"/></member>
<member><xref linkend="sql-dropprocedure"/></member>
<member><xref linkend="sql-alterroutine"/></member>
</simplelist>
<para>
Note that there is no <literal>CREATE ROUTINE</literal> command.
</para>
</refsect1>
</refentry>