Re: Wierd Explain
Martijn van Oosterhout <kleptog@svana.org>
From: Martijn van Oosterhout <kleptog@svana.org>
To: Varun Kacholia <varunk@cse.iitb.ac.in>
Cc: pgsql-general@postgresql.org
Date: 2002-06-18T08:34:25Z
Lists: pgsql-general
On Tue, Jun 18, 2002 at 12:33:26PM +0530, Varun Kacholia wrote: > hi , > Many ppl have suggested me vaccum analyze . > But the manuals say me that it is reqd after "major update/deletion". > I have just 'created' the tables and done fresh insertions. > is it still required? > BTW i am using 7.1.3 ... seems it does not support analyze :(. Fresh inserts would count as "major" since now there are values and before there wern't :). Anyway, a vacuum analyze is recommended anything you think the planner is doing something wrong. Prior to 7.2 you could only do the analyze with a vacuum, in 7.2 it was separated out Also, EXPLAIN VERBOSE could be helpful also. > On Mon, Jun 17, 2002 at 11:17:06PM +0200, Jochem van Dieten wrote: > > Varun Kacholia wrote: > > > hi , > > > I have just migrated to PostgreSQL...and found the following wierd : > > > > > > suryadb=# explain select * from dbwin where id in (select id from wdwin > > > where word='bacd'); > > > NOTICE: QUERY PLAN: > > > Seq Scan on dbwin (cost=0.00..8158.20 rows=1000 width=76) > > > > 1000 rows should trigger the obvious question: did I run vacuum analyze? > > > > Jochem -- Martijn van Oosterhout <kleptog@svana.org> http://svana.org/kleptog/ > There are 10 kinds of people in the world, those that can do binary > arithmetic and those that can't.