Re: BUG #14438: Wrong row count in the join plan with unique index scan

Thank you very much.

I see two commits:
Improve eqjoinsel_semi's behavior for small inner relat...
and
Fix bogus handling of JOIN_UNIQUE_OUTER/INNER cases...

But in the second fix parallel function is fixed.
Now we use the 9.4 postgres version in which there is no parallel select execution.
Will these changes be in the following version 9.4.x?
Will they work effectively there?

Regards,
Nikolay.

-----Original Message-----
From: Tom Lane [mailto:tgl(at)sss(dot)pgh(dot)pa(dot)us]
Sent: Wednesday, November 30, 2016 2:08 AM
To: Nikitin Nikolay
Cc: pgsql-bugs(at)postgresql(dot)org
Subject: Re: [BUGS] BUG #14438: Wrong row count in the join plan with unique index scan

nikolay(dot)nikitin(at)infowatch(dot)com writes:
> I execute select with "in" condition on the empty table.
> This select works with wrong plan.
> I think the wrong plan is chosen becose the postgres optimizer incorrectly
> calculates row count in the right plan.

I've pushed a patch that should improve matters for such cases.
Thanks for the report!

regards, tom lane