On Saturday November 6 2004 7:34, Net Virtual Mailing Lists wrote:
> Is there a way to create an index that would make this query be efficient
> and not perform a sequential scan?
>
> SELECT count(*) AS count,id FROM sometable GROUP BY id;
>
> .. I've considered creating a rule on this table which would put the
> results of this into another table anytime it is updated, but I thought
> there might be an easier way.
Since you have no "WHERE" clause and you want to group by id, I believe
pgsql has to scan all id values. Those id values are only fully stored in
the table, so I don't think so.
Ed