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<!--
doc/src/sgml/ref/drop_table.sgml
PostgreSQL documentation
-->
<refentry id="sql-droptable">
<indexterm zone="sql-droptable">
<primary>DROP TABLE</primary>
</indexterm>
<refmeta>
<refentrytitle>DROP TABLE</refentrytitle>
<manvolnum>7</manvolnum>
<refmiscinfo>SQL - Language Statements</refmiscinfo>
</refmeta>
<refnamediv>
<refname>DROP TABLE</refname>
<refpurpose>remove a table</refpurpose>
</refnamediv>
<refsynopsisdiv>
<synopsis>
DROP TABLE [ IF EXISTS ] <replaceable class="parameter">name</replaceable> [, ...] [ CASCADE | RESTRICT ]
</synopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>
<command>DROP TABLE</command> removes tables from the database.
Only the table owner, the schema owner, and superuser can drop a
table. To empty a table of rows
without destroying the table, use <link linkend="sql-delete"><command>DELETE</command></link>
or <link linkend="sql-truncate"><command>TRUNCATE</command></link>.
</para>
<para>
<command>DROP TABLE</command> always removes any indexes, rules,
triggers, and constraints that exist for the target table.
However, to drop a table that is referenced by a view or a foreign-key
constraint of another table, <literal>CASCADE</literal> must be
specified. (<literal>CASCADE</literal> will remove a dependent view entirely,
but in the foreign-key case it will only remove the foreign-key
constraint, not the other table entirely.)
</para>
</refsect1>
<refsect1>
<title>Parameters</title>
<variablelist>
<varlistentry>
<term><literal>IF EXISTS</literal></term>
<listitem>
<para>
Do not throw an error if the table 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 table to drop.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>CASCADE</literal></term>
<listitem>
<para>
Automatically drop objects that depend on the table (such as
views),
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 table if any objects depend on it. This is
the default.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Examples</title>
<para>
To destroy two tables, <literal>films</literal> and
<literal>distributors</literal>:
<programlisting>
DROP TABLE films, distributors;
</programlisting></para>
</refsect1>
<refsect1>
<title>Compatibility</title>
<para>
This command conforms to the SQL standard, except that the standard only
allows one table to be dropped per command, and apart from the
<literal>IF EXISTS</literal> option, which is a <productname>PostgreSQL</productname>
extension.
</para>
</refsect1>
<refsect1>
<title>See Also</title>
<simplelist type="inline">
<member><xref linkend="sql-altertable"/></member>
<member><xref linkend="sql-createtable"/></member>
</simplelist>
</refsect1>
</refentry>
|
