am Tue, dem 23.01.2007, um 11:34:52 +0100 mailte Laurent Manchon folgendes: > Hi, > > I have a slow response of my PostgreSQL database 7.4 using this query below > on a table with 800000 rows: > > select count(*)from tbl; If i remember correctly, i saw this question yesterday on an other list... Answer: Because PG force a sequencial scan. You can read a lot about this in the archives. Here some links to explanations: http://www.pervasive-postgres.com/instantkb13/article.aspx?id=10117&cNode=0T1L6L http://sql-info.de/postgresql/postgres-gotchas.html#1_7 http://www.varlena.com/GeneralBits/49.php Hope that helps, Andreas -- Andreas Kretschmer Kontakt: Heynitz: 035242/47150, D1: 0160/7141639 (mehr: -> Header) GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
