Doc patch in response to bug raised:
[BUGS] partial indexes not used on
parameterized queries?
10 July 2006
--
Simon Riggs
EnterpriseDB http://www.enterprisedb.com
Index: doc/src/sgml/indices.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/indices.sgml,v
retrieving revision 1.57
diff -c -r1.57 indices.sgml
*** doc/src/sgml/indices.sgml 24 May 2006 11:01:39 -0000 1.57
--- doc/src/sgml/indices.sgml 15 Aug 2006 10:22:57 -0000
***************
*** 668,674 ****
<quote>x < 1</quote> implies <quote>x < 2</quote>; otherwise
the predicate condition must exactly match part of the query's
<literal>WHERE</> condition
! or the index will not be recognized to be usable.
</para>
<para>
--- 668,679 ----
<quote>x < 1</quote> implies <quote>x < 2</quote>; otherwise
the predicate condition must exactly match part of the query's
<literal>WHERE</> condition
! or the index will not be recognized to be usable. Matching takes
! place at query planning time, not at run time. As a result,
! parameterised query clauses will not work with a partial index. For
! example a prepared query with a parameter might specify
! <quote>x < ?</quote> which will never imply
! <quote>x < 2</quote> for all possible values of the parameter.
</para>
<para>
---------------------------(end of broadcast)---------------------------
TIP 9: In versions below 8.0, the planner will ignore your desire to
choose an index scan if your joining column's datatypes do not
match