| From: | Vik Fearing <vik(dot)fearing(at)2ndquadrant(dot)com> |
|---|---|
| To: | PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org> |
| Subject: | Optimize constant MinMax expressions |
| Date: | 2018-12-29 21:40:14 |
| Message-ID: | c6e8504c-4c43-35fa-6c8f-3c0b80a912cc@2ndquadrant.com |
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| Lists: | pgsql-hackers |
I was working on a little thing where I needed to simulate BETWEEN
SYMMETRIC so naturally I used least() and greatest(). I was a little
surprised to see that my expressions were not folded into straight
constants and the estimates were way off as a consequence.
I came up with the attached patch to fix it, but it's so ridiculously
small that I fear I'm missing something.
I don't think this needs any documentation and I didn't see where we
have any existing tests for eval_const_expressions so I didn't create
any either.
Thoughts?
--
Vik Fearing +33 6 46 75 15 36
http://2ndQuadrant.fr PostgreSQL : Expertise, Formation et Support
| Attachment | Content-Type | Size |
|---|---|---|
| optimize_constant_least_greatest.v01.patch | text/x-patch | 436 bytes |
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