On Sat, 26 Mar 2005, Karim Nassar wrote:
> On Sat, 2005-03-26 at 07:55 -0800, Stephan Szabo wrote:
> > That seems like it should be okay, hmm, what does something like:
> >
> > PREPARE test(int) AS SELECT 1 from measurement where
> > id_int_sensor_meas_type = $1 FOR UPDATE;
> > EXPLAIN ANALYZE EXECUTE TEST(1);
> >
> > give you as the plan?
>
> QUERY PLAN
> -----------------------------------------------------------------------------------------------------------------------
> Seq Scan on measurement (cost=0.00..164559.16 rows=509478 width=6)
> (actual time=11608.402..11608.402 rows=0 loops=1)
> Filter: (id_int_sensor_meas_type = $1)
> Total runtime: 11608.441 ms
> (3 rows)
Hmm, has measurement been analyzed recently? You might want to see if
raising the statistics target on measurement.id_int_sensor_meas_type and
reanalyzing changes the estimated rows down from 500k.
---------------------------(end of broadcast)---------------------------
TIP 9: the planner will ignore your desire to choose an index scan if your
joining column's datatypes do not match
