From: | Peter Eisentraut <peter_e(at)gmx(dot)net> |
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To: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
Cc: | Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us>, Zeugswetter Andreas SB <ZeugswetterA(at)wien(dot)spardat(dot)at>, PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: AW: pg_index.indislossy |
Date: | 2001-07-10 16:20:52 |
Message-ID: | Pine.LNX.4.30.0107101816580.677-100000@peter.localdomain |
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Lists: | pgsql-hackers |
Tom Lane writes:
> Not true at all. The tuple commit status needs to be rechecked, yes,
> but with a normal index it is not necessary to recheck whether the index
> key field actually satisfies the index qual conditions. With a lossy
> index it *is* necessary to recheck --- the index may return more tuples
> than the ones that match the given qual.
Okay, this is not surprising. I agree that storing this in the index
might be suboptimal.
But why is this called lossy? Shouldn't it be called "exceedy"?
--
Peter Eisentraut peter_e(at)gmx(dot)net http://funkturm.homeip.net/~peter
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