Date: Fri, 11 Apr 2008 12:41:15 +0200
To: "kevin kempter" <kevin@kevinkempterllc.com>,
	pgsql-performance@postgresql.org
Subject: Re: Partitioned tables - planner wont use indexes
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> 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=3D# explain SELECT min(logdate) FROM part_master;

	Proposals :

	1- Use plpgsql to parse the system catalogs, get the list of partitions=
,  =

and issue a min() query against each
	2- Since dates tend to be incrementing, I guess the minimum date must n=
ot  =

be changing that often (unless you delete rows) ; therefore if you need =
 =

that information often I suggest a trigger that updates a separate table=
  =

which keeps the min_date (perhaps global or for each client, you choose)=
.