Cost Based Optimizer
Date: 1996/07/17
Message-ID: <4sjj4h$g13_at_hil-news-svc-4.compuserve.com>#1/1
We have a 7.1.3.2.1 production system and have just ANALYZED all the
tables and indexes.
Since we have done this we are suffering with response times from queries
that join two and more tables.
When EXPAINed/TKPROFed we have discovered that some selects are
performing full tables scans.
It appears that the execution plans worked out by the optimizer are not
the best.
(I have checked that all the tables and indexes are analyzed -
the statistics were ESTIMATEd on all but one table which was be
COMPUTEd.)
To try and solve this we have put in HINTS but to one avail.
Is there anyone out there who has knowledge of the COST based optimizer or who could offer some advise ?
Has anyone had similar problems ? and may be gone back to using the RULE based optimizer ? Received on Wed Jul 17 1996 - 00:00:00 CEST