Re: feature request: explain "with details" option - Mailing list pgsql-hackers

From Tom Lane
Subject Re: feature request: explain "with details" option
Date
Msg-id 14917.1473711919@sss.pgh.pa.us
Whole thread Raw
In response to Re: feature request: explain "with details" option  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> I think the only part of this that would be really brutal to try to
> represent is alternative join orders.  I see no reasonable way for
> EXPLAIN to output useful information about what other join orders were
> considered and why they were not chosen; the only thing that seems
> like it would help in that case would be an easy way to force the
> exact join order you want and then see what the plan looks like.

That exists today: write your query as a nest of explicit JOIN syntax
and set join_collapse_limit = 1.  Not sure that it's really all that
useful, though.
        regards, tom lane



pgsql-hackers by date:

Previous
From: Andres Freund
Date:
Subject: Re: Logical Replication WIP
Next
From: Peter Eisentraut
Date:
Subject: Re: identity columns