On Fri, Nov 18, 2005 at 09:58:24AM -0500, Tom Lane wrote:
> "Joshua D. Drake" <[EMAIL PROTECTED]> writes:
> > It appears that predicate indexes won't uses indexes on int8 columns
> > unless they are casted:
>
> This is a known (although perhaps not well documented) limitation of the
> predicate testing logic. You do not need a cast in the query, though,
> only in the index's WHERE condition.
I'm working on a docs patch for this (attached, but un-tested); is
bigint the only datatype this applies to or are there others?
--
Jim C. Nasby, Sr. Engineering Consultant [EMAIL PROTECTED]
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461
Index: doc/src/sgml/indices.sgml
===================================================================
RCS file: /projects/cvsroot/pgsql/doc/src/sgml/indices.sgml,v
retrieving revision 1.55
diff -u -r1.55 indices.sgml
--- doc/src/sgml/indices.sgml 7 Nov 2005 17:36:44 -0000 1.55
+++ doc/src/sgml/indices.sgml 22 Nov 2005 00:30:55 -0000
@@ -525,6 +525,16 @@
feature, but there are several situations in which they are useful.
</para>
+ <note>
+ <para>
+ Predicate indexes on bigint (<xref linkend="datatype-int">) columns will
+ not be used unless they are casted:
+<programlisting>
+CREATE INDEX foo ON test_key (id) WHERE id >= 50000::bigint;
+</programlisting>
+ </para>
+ </note>
+
<para>
One major reason for using a partial index is to avoid indexing common
values. Since a query searching for a common value (one that
---------------------------(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
