Re: Query planner wants to use seq scan

I did the test yesterday with an index on the three fields, and with a partial index on organization and status and where is null condition on handled.

Le mardi 27 octobre 2015, Tom Lane <tgl@sss.pgh.pa.us> a écrit :

Bertrand Paquet <bertrand.paquet@doctolib.fr> writes:
> We have a slow query. After analyzing, the planner decision seems to be
> discutable : the query is faster when disabling seqscan. See below the two
> query plan, and an extract from pg_stats.

> Any idea about what to change to help the planner ?

Neither one of those plans is very good: you're just hoping that the
Filter condition will let a tuple through sooner rather than later.

If you care about the performance of this type of query, I'd consider
creating an index on (organization_id, status, handled_by) so that all
the conditions can be checked in the index.

                        regards, tom lane