| From: | "Christopher Kings-Lynne" <chriskl(at)familyhealth(dot)com(dot)au> |
|---|---|
| To: | "Stephan Szabo" <sszabo(at)megazone23(dot)bigpanda(dot)com> |
| Cc: | "Daniele Orlandi" <daniele(at)orlandi(dot)com>, <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: Optimizer & boolean syntax |
| Date: | 2002-11-21 22:45:34 |
| Message-ID: | 004f01c291af$b435e350$6600a8c0@internal |
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| Lists: | pgsql-hackers |
> > I think his point is that they _should_ be equivalent. Surely there's
> > something in the optimiser that discards '=true' stuff, like 'a=a'
should be
> > discarded?
>
> I figure that's what he meant, but it isn't what was said. ;)
>
> "col" isn't of the general form "indexkey op constant" or "constant op
> indexkey" which I presume it's looking for given the comments in
> indxpath.c. I'm not sure what the best way to make it work would be given
> that presumably we'd want to make col IS TRUE/FALSE use an index at the
> same time (since that appears to not do so as well).
Not that I see the point of indexing booleans, but hey :)
Chris
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