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<!--
doc/src/sgml/ref/drop_type.sgml
PostgreSQL documentation
-->
<refentry id="sql-droptype">
<indexterm zone="sql-droptype">
<primary>DROP TYPE</primary>
</indexterm>
<refmeta>
<refentrytitle>DROP TYPE</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>DROP TYPE</refname>
<refpurpose>remove a data type</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
DROP TYPE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> [, ...] [ CASCADE | RESTRICT ]
</synopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
<command>DROP TYPE</command> removes a user-defined data type.
Only the owner of a type can remove it.
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><literal>IF EXISTS</literal></term>
<listitem>
<para>
Do not throw an error if the type does not exist. A notice is issued
in this case.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><replaceable class="parameter">name</replaceable></term>
<listitem>
<para>
The name (optionally schema-qualified) of the data type to remove.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>CASCADE</literal></term>
<listitem>
<para>
Automatically drop objects that depend on the type (such as
table columns, functions, and operators),
and in turn all objects that depend on those objects
(see <xref linkend="ddl-depend"/>).
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>RESTRICT</literal></term>
<listitem>
<para>
Refuse to drop the type if any objects depend on it. This is
the default.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="sql-droptype-examples">
<title>Examples</title>
<para>
To remove the data type <type>box</type>:
<programlisting>
DROP TYPE box;
</programlisting></para>
</refsect1>
<refsect1 id="sql-droptype-compatibility">
<title>Compatibility</title>
<para>
This command is similar to the corresponding command in the SQL
standard, apart from the <literal>IF EXISTS</literal>
option, which is a <productname>PostgreSQL</productname> extension.
But note that much of the <command>CREATE TYPE</command> command
and the data type extension mechanisms in
<productname>PostgreSQL</productname> differ from the SQL standard.
</para>
</refsect1>
<refsect1 id="sql-droptype-see-also">
<title>See Also</title>
<simplelist type="inline">
<member><xref linkend="sql-altertype"/></member>
<member><xref linkend="sql-createtype"/></member>
</simplelist>
</refsect1>
</refentry>
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