Re: Proposed patch to make mergejoin cost estimation more symmetric - Mailing list pgsql-patches

From Gregory Stark
Subject Re: Proposed patch to make mergejoin cost estimation more symmetric
Date
Msg-id 87bq92q305.fsf@oxford.xeocode.com
Whole thread Raw
In response to Proposed patch to make mergejoin cost estimation more symmetric  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Proposed patch to make mergejoin cost estimation more symmetric
List pgsql-patches
"Tom Lane" <tgl@sss.pgh.pa.us> writes:

> Any objections to applying the patch?

I like applying it.

You don't include any negative tests and corner cases as well; cases where the
new code shouldn't be disturbing the results such as a symmetric join or a
join against a single-row table. The comments make me think you ran them but
just didn't show them though.

What about a merge join against an empty table? I suppose there would just be
no statistics?


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  Gregory Stark
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