Re: [PERFORM] Partitioned tables - planner wont use indexes

2008-04-11 Thread PFC
I tried removing the index from the part_master table and got the same result Since all the data is in the partitions, the part_master table is empty, so the index is not useful for your query. myDB=# explain SELECT min(logdate) FROM part_master; Proposals : 1- Use plpgsql t

[PERFORM] Partitioned tables - planner wont use indexes

2008-04-10 Thread kevin kempter
Hi List; I'm having some performance issues with a partitioned table. We have a VERY large table that we've partitioned by day. Currently we have 17 partitions - each partition table contains > 700million rows. One of the things we need to query is the min date from the master table - we

Re: [PERFORM] Partitioned tables - planner wont use indexes

2008-04-07 Thread Bricklen Anderson
kevin kempter wrote: One of the things we need to query is the min date from the master table - we may explore alternatives for this particular query, however even if we fix this query I think we have a fundamental issue with the use of indexes (actuallt the non-use) by the planner. We had a

Re: [PERFORM] Partitioned tables - planner wont use indexes

2008-04-04 Thread Gregory Stark
"kevin kempter" <[EMAIL PROTECTED]> writes: > that the planner wants to do a sequential scan on each partition. We do have > "constraint_elimination = on" set in the postgresql.conf file. "constraint_exclusion" btw. > myDB=# explain SELECT min(logdate) FROM part_master; Er, yeah. Unfortunat

Re: [PERFORM] Partitioned tables - planner wont use indexes

2008-04-04 Thread paul rivers
kevin kempter wrote: Hi List; Sorry if this is a dupe, my first post never showed up... I'm having some performance issues with a partitioned table. We have a VERY large table that we've partitioned by day. Unfortunately, that is the defined behavior in this case. From 5.9.6 of the manual

[PERFORM] Partitioned tables - planner wont use indexes

2008-04-04 Thread kevin kempter
Hi List; Sorry if this is a dupe, my first post never showed up... I'm having some performance issues with a partitioned table. We have a VERY large table that we've partitioned by day. Currently we have 17 partitions - each partition table contains > 700million rows. One of the things we