|
|
@ -1,5 +1,5 @@ |
|
|
|
<!-- |
|
|
|
<!-- |
|
|
|
$PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.105 2005/10/14 20:48:18 adunstan Exp $ |
|
|
|
$PostgreSQL: pgsql/doc/src/sgml/xfunc.sgml,v 1.106 2005/10/15 01:47:12 neilc Exp $ |
|
|
|
--> |
|
|
|
--> |
|
|
|
|
|
|
|
|
|
|
|
<sect1 id="xfunc"> |
|
|
|
<sect1 id="xfunc"> |
|
|
@ -881,9 +881,9 @@ CREATE FUNCTION test(int, int) RETURNS int |
|
|
|
Every function has a <firstterm>volatility</> classification, with |
|
|
|
Every function has a <firstterm>volatility</> classification, with |
|
|
|
the possibilities being <literal>VOLATILE</>, <literal>STABLE</>, or |
|
|
|
the possibilities being <literal>VOLATILE</>, <literal>STABLE</>, or |
|
|
|
<literal>IMMUTABLE</>. <literal>VOLATILE</> is the default if the |
|
|
|
<literal>IMMUTABLE</>. <literal>VOLATILE</> is the default if the |
|
|
|
<command>CREATE FUNCTION</command> command does not specify a category. |
|
|
|
<xref linkend="sql-createfunction" endterm="sql-createfunction-title"> |
|
|
|
The volatility category is a promise to the optimizer about the behavior |
|
|
|
command does not specify a category. The volatility category is a |
|
|
|
of the function: |
|
|
|
promise to the optimizer about the behavior of the function: |
|
|
|
|
|
|
|
|
|
|
|
<itemizedlist> |
|
|
|
<itemizedlist> |
|
|
|
<listitem> |
|
|
|
<listitem> |
|
|
@ -1180,8 +1180,9 @@ CREATE FUNCTION square_root(double precision) RETURNS double precision |
|
|
|
file is retained in memory. Future calls in the same session to |
|
|
|
file is retained in memory. Future calls in the same session to |
|
|
|
the function(s) in that file will only incur the small overhead of |
|
|
|
the function(s) in that file will only incur the small overhead of |
|
|
|
a symbol table lookup. If you need to force a reload of an object |
|
|
|
a symbol table lookup. If you need to force a reload of an object |
|
|
|
file, for example after recompiling it, use the <command>LOAD</> |
|
|
|
file, for example after recompiling it, use the <xref |
|
|
|
command or begin a fresh session. |
|
|
|
linkend="sql-load" endterm="sql-load-title"> command or begin a |
|
|
|
|
|
|
|
fresh session. |
|
|
|
</para> |
|
|
|
</para> |
|
|
|
|
|
|
|
|
|
|
|
<para> |
|
|
|
<para> |
|
|
@ -1652,7 +1653,7 @@ CREATE FUNCTION copytext(text) RETURNS text |
|
|
|
LANGUAGE C STRICT; |
|
|
|
LANGUAGE C STRICT; |
|
|
|
|
|
|
|
|
|
|
|
CREATE FUNCTION concat_text(text, text) RETURNS text |
|
|
|
CREATE FUNCTION concat_text(text, text) RETURNS text |
|
|
|
AS '<replaceable>DIRECTORY</replaceable>/funcs', 'concat_text', |
|
|
|
AS '<replaceable>DIRECTORY</replaceable>/funcs', 'concat_text' |
|
|
|
LANGUAGE C STRICT; |
|
|
|
LANGUAGE C STRICT; |
|
|
|
</programlisting> |
|
|
|
</programlisting> |
|
|
|
</para> |
|
|
|
</para> |
|
|
|