Re: [PERFORM] select count(*) on large tables

2004-04-08 Thread Tom Lane
Cosimo Streppone <[EMAIL PROTECTED]> writes: > Is there an estimate time for this issue to be resolved? Approximately never. It's a fundamental feature of Postgres' design. As noted by Dennis, you can look at the pg_class statistics if a recent estimate is good enough, or you can build user-leve

Re: [PERFORM] select count(*) on large tables

2004-04-08 Thread Dennis Bjorklund
On Thu, 8 Apr 2004, Cosimo Streppone wrote: > The alternative solution I tried, that has an optimal > speed up, unfortunately is not a way out, and it is based > on "EXPLAIN SELECT count(*)" output parsing, which > is obviously *not* reliable. Try this to get the estimate: SELECT relname, rel

[PERFORM] select count(*) on large tables

2004-04-08 Thread Cosimo Streppone
Hello, I've followed the last discussion about the particular case of "select count(*)"s on large tables being somewhat slow. I've seen also this issue already on the todo list, so I know it is not a simple question. This problem arises for me on very large tables, which I mean starting from 1 mil