You can also try this one:
ANALYZE tablename;
select reltuples from pg_class where relname = 'tablename';
Will also give almost the same results I guess...
-------------
Shoaib Mir
EnterpriseDB (
www.enterprisedb.com)
On 1/23/07, Bruno Wolff III <bruno@wolff.to> wrote: On Tue, Jan 23, 2007 at 11:34:52 +0100,
Laurent Manchon < lmanchon@univ-montp2.fr> wrote:
> 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;
>
> PostgreSQL return result in 28 sec every time.
> although MS-SQL return result in 0.02 sec every time.
Besides the other advice mentioned in this thread, check that you don't
have a lot of dead tuples in that table. 28 seconds seems a bit high
for even a sequential scan of 800000 tuples unless they are pretty large.
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