Hi we are testing with version PostgreSQL 8.2.3. We already have a production system in Oracle and we wanted to migrate it to postgresql. If some tests are already done, are the results available for us to see? Ill also check postgres 8.3 beta. Thanks again Sharmila
----- Original Message ---- From: Simon Riggs <[EMAIL PROTECTED]> To: Bill Moran <[EMAIL PROTECTED]> Cc: SHARMILA JOTHIRAJAH <[EMAIL PROTECTED]>; pgsql-general@postgresql.org Sent: Wednesday, November 7, 2007 6:34:26 AM Subject: Re: [GENERAL] Postgresql simple query performance question On Tue, 2007-11-06 at 09:29 -0500, Bill Moran wrote: > In response to SHARMILA JOTHIRAJAH <[EMAIL PROTECTED]>: > > > Hi > > We are in the process of testing for migration of our database from Oracle to Postgresql. > > I hava a simple query > > > > Select count(*) from foo > > This is asked a lot. The quick answer is that PostgreSQL method of MVCC > makes it impossible to make this query fast. Perhaps, someday, some > brilliant developer will come up with an optimization, but that hasn't > happened yet. What release level is being tested? It may already have happened. 8.3 is substantially faster at seq scans, so the tests should be re-run on 8.3 beta. Also, re-run the Postgres test. It should be faster the second time, even if the database server is restarted between tests. -- Simon Riggs 2ndQuadrant http://www.2ndQuadrant.com ---------------------------(end of broadcast)--------------------------- TIP 5: don't forget to increase your free space map settings __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com