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128 lines
2.7 KiB
Plaintext
128 lines
2.7 KiB
Plaintext
<!-- $Header: /cvsroot/pgsql/doc/src/sgml/ref/drop_cast.sgml,v 1.2 2002/08/11 17:44:12 petere Exp $ -->
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<refentry id="SQL-DROPCAST">
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<refmeta>
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<refentrytitle id="SQL-DROPCAST-TITLE">DROP CAST</refentrytitle>
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<refmiscinfo>SQL - Language Statements</refmiscinfo>
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</refmeta>
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<refnamediv>
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<refname>DROP CAST</refname>
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<refpurpose>remove a user-defined cast</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<synopsis>
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DROP CAST (<replaceable>sourcetype</replaceable> AS <replaceable>targettype</replaceable>)
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[ CASCADE | RESTRICT ]
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</synopsis>
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</refsynopsisdiv>
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<refsect1 id="sql-dropcast-description">
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<title>Description</title>
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<para>
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<command>DROP CAST</command> removes a previously defined cast.
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</para>
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<para>
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To be able to drop a cast, you must own the source or the target
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data type. These are the same privileges that are required to
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create a cast.
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</para>
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<variablelist>
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<title>Parameters</title>
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<varlistentry>
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<term><replaceable>sourcetype</replaceable></term>
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<listitem>
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<para>
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The name of the source data type of the cast.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><replaceable>targettype</replaceable></term>
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<listitem>
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<para>
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The name of the target data type of the cast.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><literal>CASCADE</literal></term>
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<term><literal>RESTRICT</literal></term>
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<listitem>
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<para>
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These key words do not have any effect, since there are no
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dependencies on casts.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsect1 id="sql-dropcast-notes">
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<title>Notes</title>
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<para>
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Use <command>CREATE CAST</command> to create user-defined casts.
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</para>
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</refsect1>
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<refsect1 id="sql-dropcast-examples">
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<title>Examples</title>
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<para>
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To drop the cast from type <type>text</type> to type <type>int</type>:
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<programlisting>
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DROP CAST (text AS int4);
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</programlisting>
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</para>
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</refsect1>
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<refsect1 id="sql-dropcast-compat">
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<title>Compatibility</title>
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<para>
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The <command>DROP CAST</command> command conforms to SQL99.
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</para>
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</refsect1>
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<refsect1 id="sql-dropcast-seealso">
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<title>See Also</title>
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<para>
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<xref linkend="sql-createcast" endterm="sql-createcast-title">
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</para>
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</refsect1>
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</refentry>
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<!-- Keep this comment at the end of the file
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Local variables:
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mode:sgml
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sgml-omittag:nil
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sgml-shorttag:t
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sgml-minimize-attributes:nil
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sgml-always-quote-attributes:t
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sgml-indent-step:1
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sgml-indent-data:t
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sgml-parent-document:nil
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sgml-default-dtd-file:"../reference.ced"
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sgml-exposed-tags:nil
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sgml-local-catalogs:("/usr/lib/sgml/catalog")
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sgml-local-ecat-files:nil
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End:
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-->
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