| From: | Alvaro Herrera <alvherre(at)dcc(dot)uchile(dot)cl> |
|---|---|
| To: | Christopher Kings-Lynne <chriskl(at)familyhealth(dot)com(dot)au> |
| Cc: | Stephan Szabo <sszabo(at)megazone23(dot)bigpanda(dot)com>, Daniele Orlandi <daniele(at)orlandi(dot)com>, pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: Optimizer & boolean syntax |
| Date: | 2002-11-21 22:55:54 |
| Message-ID: | 20021121225554.GD12021@dcc.uchile.cl |
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| Lists: | pgsql-hackers |
On Thu, Nov 21, 2002 at 02:45:34PM -0800, Christopher Kings-Lynne wrote:
> > > 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?
> Not that I see the point of indexing booleans, but hey :)
If one of the values is much more infrequent than the other, you can
probably get a substantial win using a partial index, can't you?
--
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
"Everybody understands Mickey Mouse. Few understand Hermann Hesse.
Hardly anybody understands Einstein. And nobody understands Emperor Norton."
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