"Theo Petersen" <tpetersen@ocv.com> writes:
> I have a database (network monitoring data created by OpenNMS) that exhibits
> this behavior:
>
> 1) I restore the database from a production backup.
> 2) I perform a select that joins four tables, and get 9 rows of output.
> 3) I use the command VACUUM ANALYZE to maintain the database files.
> 4) I perform the same select and get 0 rows of output.
>
> I've reduced it to those steps to verify the problem.
Are you perchance doing joins involving INET or CIDR types where
the old database is 7.3.x and the new database is 7.4.x? I ask
because I discovered a problem with the 7.4.x = operator when I was
(hastily) writing the prototype for the application I think you're
working on.
http://archives.postgresql.org/pgsql-general/2004-04/msg00453.php
If this is the problem you're having, then it should be mentioned
on the project Wiki that Chris F. set up, if it still exists.
--
Michael Fuhr
http://www.fuhr.org/~mfuhr/