diff options
Diffstat (limited to 'doc/src')
| -rw-r--r-- | doc/src/sgml/plpython.sgml | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/doc/src/sgml/plpython.sgml b/doc/src/sgml/plpython.sgml index f42c17e6fb0..7a36c074dca 100644 --- a/doc/src/sgml/plpython.sgml +++ b/doc/src/sgml/plpython.sgml @@ -1,4 +1,4 @@ -<!-- $Header: /cvsroot/pgsql/doc/src/sgml/plpython.sgml,v 1.14 2002/09/23 01:51:02 momjian Exp $ --> +<!-- $Header: /cvsroot/pgsql/doc/src/sgml/plpython.sgml,v 1.15 2002/10/21 20:34:09 momjian Exp $ --> <chapter id="plpython"> <title>PL/Python - Python Procedural Language</title> @@ -198,15 +198,24 @@ rv = plpy.execute(plan, [ "name" ], 5) <para> When you prepare a plan using the PL/Python module it is automatically saved. Read the SPI documentation (<xref - linkend="spi">) for a description of what this means. The take - home message is if you do + linkend="spi">) for a description of what this means. + </para> + + <para> + In order to make effective use of this across function calls + one needs to use one of the persistent storage dictionaries + <literal>SD</literal> or <literal>GD</literal>, see + <xref linkend="plpython-funcs">. For example: <programlisting> -plan = plpy.prepare("SOME QUERY") -plan = plpy.prepare("SOME OTHER QUERY") +CREATE FUNCTION usesavedplan ( ) RETURNS TRIGGER AS ' + if SD.has_key("plan"): + plan = SD["plan"] + else: + plan = plpy.prepare("SELECT 1") + SD["plan"] = plan + # rest of function +' LANGUAGE 'plpython'; </programlisting> - you are leaking memory, as I know of no way to free a saved plan. - The alternative of using unsaved plans it even more painful (for - me). </para> </sect1> |