Re: merge join killing performance - Mailing list pgsql-performance

From Tom Lane
Subject Re: merge join killing performance
Date
Msg-id 3829.1274365692@sss.pgh.pa.us
Whole thread Raw
In response to Re: merge join killing performance  (Scott Marlowe <scott.marlowe@gmail.com>)
Responses Re: merge join killing performance  (Scott Marlowe <scott.marlowe@gmail.com>)
List pgsql-performance
Scott Marlowe <scott.marlowe@gmail.com> writes:
> So, Tom, so you think it's possible that the planner isn't noticing
> all those nulls and thinks it'll just take a row or two to get to the
> value it needs to join on?

Could be.  I don't have time right now to chase through the code, but
that sounds like a plausible theory.

            regards, tom lane

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