mirror of https://github.com/postgres/postgres
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
145 lines
3.6 KiB
145 lines
3.6 KiB
<!--
|
|
$PostgreSQL: pgsql/doc/src/sgml/ref/delete.sgml,v 1.21 2005/01/04 00:39:53 tgl Exp $
|
|
PostgreSQL documentation
|
|
-->
|
|
|
|
<refentry id="SQL-DELETE">
|
|
<refmeta>
|
|
<refentrytitle id="SQL-DELETE-TITLE">DELETE</refentrytitle>
|
|
<refmiscinfo>SQL - Language Statements</refmiscinfo>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>DELETE</refname>
|
|
<refpurpose>delete rows of a table</refpurpose>
|
|
</refnamediv>
|
|
|
|
<indexterm zone="sql-delete">
|
|
<primary>DELETE</primary>
|
|
</indexterm>
|
|
|
|
<refsynopsisdiv>
|
|
<synopsis>
|
|
DELETE FROM [ ONLY ] <replaceable class="PARAMETER">table</replaceable> [ WHERE <replaceable class="PARAMETER">condition</replaceable> ]
|
|
</synopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
<command>DELETE</command> deletes rows that satisfy the
|
|
<literal>WHERE</literal> clause from the specified table. If the
|
|
<literal>WHERE</literal> clause is absent, the effect is to delete
|
|
all rows in the table. The result is a valid, but empty table.
|
|
</para>
|
|
|
|
<tip>
|
|
<para>
|
|
<xref linkend="sql-truncate" endterm="sql-truncate-title"> is a
|
|
<productname>PostgreSQL</productname> extension that provides a
|
|
faster mechanism to remove all rows from a table.
|
|
</para>
|
|
</tip>
|
|
|
|
<para>
|
|
By default, <command>DELETE</command> will delete rows in the
|
|
specified table and all its subtables. If you wish to delete only
|
|
from the specific table mentioned, you must use the
|
|
<literal>ONLY</literal> clause.
|
|
</para>
|
|
|
|
<para>
|
|
You must have the <literal>DELETE</literal> privilege on the table
|
|
to delete from it, as well as the <literal>SELECT</literal>
|
|
privilege for any table whose values are read in the <replaceable
|
|
class="parameter">condition</replaceable>.
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Parameters</title>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><replaceable class="parameter">table</replaceable></term>
|
|
<listitem>
|
|
<para>
|
|
The name (optionally schema-qualified) of an existing table.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><replaceable class="parameter">condition</replaceable></term>
|
|
<listitem>
|
|
<para>
|
|
A value expression that returns a value of type
|
|
<type>boolean</type> that determines the rows which are to be
|
|
deleted.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Outputs</title>
|
|
|
|
<para>
|
|
On successful completion, a <command>DELETE</> command returns a command
|
|
tag of the form
|
|
<screen>
|
|
DELETE <replaceable class="parameter">count</replaceable>
|
|
</screen>
|
|
The <replaceable class="parameter">count</replaceable> is the number
|
|
of rows deleted. If <replaceable class="parameter">count</replaceable> is
|
|
0, no rows matched the <replaceable
|
|
class="parameter">condition</replaceable> (this is not considered
|
|
an error).
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Examples</title>
|
|
|
|
<para>
|
|
Delete all films but musicals:
|
|
<programlisting>
|
|
DELETE FROM films WHERE kind <> 'Musical';
|
|
</programlisting>
|
|
</para>
|
|
|
|
<para>
|
|
Clear the table <literal>films</literal>:
|
|
<programlisting>
|
|
DELETE FROM films;
|
|
</programlisting>
|
|
</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Compatibility</title>
|
|
|
|
<para>
|
|
This command conforms to the SQL standard.
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|
|
|
|
<!-- Keep this comment at the end of the file
|
|
Local variables:
|
|
mode: sgml
|
|
sgml-omittag:nil
|
|
sgml-shorttag:t
|
|
sgml-minimize-attributes:nil
|
|
sgml-always-quote-attributes:t
|
|
sgml-indent-step:1
|
|
sgml-indent-data:t
|
|
sgml-parent-document:nil
|
|
sgml-default-dtd-file:"../reference.ced"
|
|
sgml-exposed-tags:nil
|
|
sgml-local-catalogs:"/usr/lib/sgml/catalog"
|
|
sgml-local-ecat-files:nil
|
|
End:
|
|
-->
|
|
|