diff options
| author | Tom Lane <tgl@sss.pgh.pa.us> | 1999-10-02 21:27:49 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 1999-10-02 21:27:49 +0000 |
| commit | e23a2b1ea02fbbb121048d5f616c397949ebdca8 (patch) | |
| tree | d69ed45b26238ddc6525d120ccad98ef18be57b5 /doc/src/sgml/ref/create_function.sgml | |
| parent | 1f122a7c4c9562dfe31b9a2c44b5b843bfca40bd (diff) | |
Document formerly-undocumented WITH clause of CREATE FUNCTION.
Diffstat (limited to 'doc/src/sgml/ref/create_function.sgml')
| -rw-r--r-- | doc/src/sgml/ref/create_function.sgml | 27 |
1 files changed, 22 insertions, 5 deletions
diff --git a/doc/src/sgml/ref/create_function.sgml b/doc/src/sgml/ref/create_function.sgml index b22b9e4088f..3fb87b57f83 100644 --- a/doc/src/sgml/ref/create_function.sgml +++ b/doc/src/sgml/ref/create_function.sgml @@ -1,5 +1,5 @@ <!-- -$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.10 1999/09/28 04:34:39 momjian Exp $ +$Header: /cvsroot/pgsql/doc/src/sgml/ref/create_function.sgml,v 1.11 1999/10/02 21:27:49 tgl Exp $ Postgres documentation --> @@ -20,19 +20,21 @@ Postgres documentation </refnamediv> <refsynopsisdiv> <refsynopsisdivinfo> - <date>1999-07-20</date> + <date>1999-10-02</date> </refsynopsisdivinfo> <synopsis> CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceable class="parameter">ftype</replaceable> [, ...] ] ) RETURNS <replaceable class="parameter">rtype</replaceable> + [ WITH ( <replaceable class="parameter">attribute</replaceable> [, ...] ) ] AS <replaceable class="parameter">definition</replaceable> LANGUAGE '<replaceable class="parameter">langname</replaceable>' CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceable class="parameter">ftype</replaceable> [, ...] ] ) RETURNS <replaceable class="parameter">rtype</replaceable> + [ WITH ( <replaceable class="parameter">attribute</replaceable> [, ...] ) ] AS <replaceable class="parameter">obj_file</replaceable> , <replaceable class="parameter">link_symbol</replaceable> - LANGUAGE 'c' + LANGUAGE 'C' </synopsis> <refsect2 id="R2-SQL-CREATEFUNCTION-1"> @@ -80,6 +82,22 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab </listitem> </varlistentry> <varlistentry> + <term><replaceable class="parameter">attribute</replaceable></term> + <listitem> + <para> + An optional piece of information about the function, used for + optimization. The only attribute currently supported is + <literal>iscachable</literal>. + <literal>iscachable</literal> indicates that the function always + returns the same result when given the same input values (i.e., + it does not do database lookups or otherwise use information not + directly present in its parameter list). The optimizer uses + <literal>iscachable</literal> to know whether it is safe to + pre-evaluate a call of the function. + </para> + </listitem> + </varlistentry> + <varlistentry> <term><replaceable class="parameter">definition</replaceable></term> <listitem> <para> @@ -113,8 +131,7 @@ CREATE FUNCTION <replaceable class="parameter">name</replaceable> ( [ <replaceab '<literal>internal</literal>' or '<replaceable class="parameter">plname</replaceable>', where '<replaceable class="parameter">plname</replaceable>' - is the name of a created procedural - language. See + is the name of a created procedural language. See <xref linkend="sql-createlanguage-title" endterm="sql-createlanguage-title"> for details. </para> |