On Fri, 2008-05-16 at 09:21 -0600, Scott Marlowe wrote: > On Thu, May 15, 2008 at 12:00 AM, <[EMAIL PROTECTED]> wrote: > > Hi, > > > > select count(distinct(j.JOBID)) as jobCount > > from JOB_TYPE_FIRST a, JOB_TYPE_SECOND b, JOB_ALLOCATION_WORKLIST j > > where (( a.JOBID = j.JOBID) > > and (a.BOOK_ID = :bookId)) > > or ((b.JOBID = j.JOBID) > > and (b.BOOK_ID = :bookId)); > > Have you tried joining a with j and b with j separately, and then > doing a union on those two sets?
That seems the only way to get a sane answer to this query, which is otherwise an unconstrained join on both sides of the OR. Great example of a query which runs slow because the question is phrased incorrectly. Count(distinct) is pretty much the only function that will give the same answer as a correctly phrased query. -- Simon Riggs www.2ndQuadrant.com PostgreSQL Training, Services and Support -- Sent via pgsql-sql mailing list (pgsql-sql@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql
