Re: Join optimisation Quandry - Mailing list pgsql-performance

From Tom Lane
Subject Re: Join optimisation Quandry
Date
Msg-id 18213.1074478860@sss.pgh.pa.us
Whole thread Raw
In response to Re: Join optimisation Quandry  (Ceri Storey <cez-misc.pgsql-perf@necrofish.org.uk>)
List pgsql-performance
Ceri Storey <cez-misc.pgsql-perf@necrofish.org.uk> writes:
> Although, as I've just found, another bottleneck is the title table.
> PostgreSQL seems to inst on doing a Seq Scan on the entire table.

>    ->  Seq Scan on tid  (cost=0.00..20.00 rows=1000 width=8) (actual time=0.028..10.457 rows=17 loops=1)

It doesn't look like you've ever vacuumed or analyzed "tid" --- those
are the default cost and rows estimates.  Although I'm unsure whether
the plan would change much if you had.

            regards, tom lane

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