Re: Seq Scan

Tyler Durden wrote:
> Hi,
> I'm having some problems in performance in a simple select count(id)
> from.... I have 700 000 records in one table, and when I do:
>
> # explain select (id) from table_name;
> -[ RECORD 1
> ]----------------------------------------------------------------
> QUERY PLAN | Seq Scan on table_name  (cost=0.00..8601.30 rows=266730
> width=4)
>
> I had created an index for id(btree), but still shows "Seq Scan".
> What I'm doing wrong?

Nothing. You have to scan the table because you aren't giving postgresql
anything to use the index by.

Joshua D. Drake

>
> Thanks,
> Tyler
>
> ---------------------------(end of broadcast)---------------------------
> TIP 6: explain analyze is your friend
>


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