Laurent Manchon wrote:
> 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.
Can you post the results of:
analyze verbose tbl;
explain analyze select count(*) from tbl;
The first will give us some info about how many pages tbl has (in 7.4
ISTR it does not state the # of dead rows... but anyway), the second
should help us deduce why it is so slow.
Also as others have pointed out, later versions are quite a bit faster
for sequential scans...
In response to
- slow result at 2007-01-23 12:34:19 from Laurent Manchon
pgsql-performance by date
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