| From: | Francisco Reyes <lists(at)natserv(dot)com> |
|---|---|
| To: | John Meinel <john(at)johnmeinel(dot)com> |
| Cc: | pgsql-performance(at)postgresql(dot)org |
| Subject: | Re: why my query is not using index?? |
| Date: | 2004-10-12 04:56:15 |
| Message-ID: | 20041012005231.U98867@zoraida.natserv.net |
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| Thread: | |
| Lists: | pgsql-performance |
On Mon, 11 Oct 2004, John Meinel wrote:
> Postgres believes that it will cost 382 to do a sequential scan, versus 490
> for an indexed scan. Hence why it prefers to do the sequential scan. Try
> running explain analyze to see if how accurate it is.
With explain analyze I have with sequential scan on
Sort (cost=382.01..382.15 rows=56 width=196)
(actual time=64.346..64.469 rows=24 loops=1)
And with seqscan off
Sort (cost=490.82..490.96 rows=56 width=196)
(actual time=56.668..56.789 rows=24 loops=1)
So I guess that for this particular query I am better off setting the
seqscan off.
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