Performance issue - Mailing list pgsql-performance

From Willo van der Merwe
Subject Performance issue
Date
Msg-id 46D2C0B0.8080101@studentvillage.co.za
Whole thread Raw
List pgsql-performance
Hi Guys,

I have something odd. I have Gallery2 running on PostgreSQL 8.1, and
recently I upgraded to 8.1.9-1.el4s1.1 (64bit). The issue here really is
how do I get PostgreSQL to work with their horrible code. The queries
they generate look something like :
SELECT blah, blah FROM table1, table2 WHERE <some relational stuff> AND
id IN (<here a list of 42000+ IDs are listed>)

On the previous version (which I can't recall what it was, but it was a
version 8.1) the queries executed fine, but suddenly now, these queries
are taking up-to 4 minutes to complete. I am convinced it's the
parsing/handling of the IN clause. It could, of course, be that the list
has grown so large that it can't fit into a buffer anymore. For obvious
reasons I can't run an EXPLAIN ANALYZE from a prompt. I vacuum and
reindex  the database daily.

I'd prefer not to have to rewrite the code, so any suggestions would be
very welcome.

Kind regards

Willo van der Merwe

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