Gaetano,
> SELECT * from user_logs where id_user in (
> 10943, 10942, 10934, 10927, 10910, 10909
> );
> [SNIPPED]
> Why the planner or the executor ( I don't know ) do not follow
> the same strategy ?
It is, actually, according to the query plan.
Can you post the EXPLAIN ANALYZE for the above query?
--
-Josh Berkus
Aglio Database Solutions
San Francisco