Re: Fwd: [PERFORM] 8.2 Query 10 times slower than 8.1 (view-heavy)

2007-08-31 Thread Tom Lane
I wrote: Mark Lewis [EMAIL PROTECTED] writes: We've been holding back from upgrading to 8.2 because this one is a show-stopper for us. Well, you could always make your own version with this patch reverted: http://archives.postgresql.org/pgsql-committers/2006-11/msg00066.php I might end up

Re: Fwd: [PERFORM] 8.2 Query 10 times slower than 8.1 (view-heavy)

2007-08-31 Thread Mark Lewis
On Fri, 2007-08-31 at 19:39 -0400, Tom Lane wrote: I wrote: Mark Lewis [EMAIL PROTECTED] writes: We've been holding back from upgrading to 8.2 because this one is a show-stopper for us. Well, you could always make your own version with this patch reverted:

Re: Fwd: [PERFORM] 8.2 Query 10 times slower than 8.1 (view-heavy)

2007-08-28 Thread Mark Lewis
It looks like your view is using a left join to look for rows in one table without matching rows in the other, i.e. a SQL construct similar in form to the query below: SELECT ... FROM A LEFT JOIN B ON (...) WHERE B.primary_key IS NULL Unfortunately there has been a planner regression in 8.2 in

Re: Fwd: [PERFORM] 8.2 Query 10 times slower than 8.1 (view-heavy)

2007-08-28 Thread Tom Lane
Mark Lewis [EMAIL PROTECTED] writes: Unfortunately there has been a planner regression in 8.2 in some cases with these forms of queries. This was discussed a few weeks (months?) ago on this forum. I haven't looked closely enough to confirm that this is the problem in your case, but it seems