Re: Performance improvement for joins where outer side is unique

David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
> On 19 January 2017 at 11:06, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
> > Old patch no longer applies, so I've attached a rebased patch. This
> > also re-adds a comment line which I mistakenly removed.
>
> (meanwhile Andres commits 69f4b9c)
>
> I should've waited a bit longer.
>
> Here's another that fixes the new conflicts.

I suspect that "inner" and "outer" relation / tuple are sometimes confused in
comments:

* analyzejoins.c:70

"searches for subsequent matching outer tuples."

* analyzejoins.c:972

/*
* innerrel_is_unique
* Check for proofs which prove that 'innerrel' can, at most, match a
* single tuple in 'outerrel' based on the join condition in
* 'restrictlist'.
*/

* relation.h:1831

bool inner_unique; /* inner side of join matches no more than one
* outer side tuple */

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Antonin Houska
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