Re: AW: pg_index.indislossy - Mailing list pgsql-hackers

From Peter Eisentraut
Subject Re: AW: pg_index.indislossy
Date
Msg-id Pine.LNX.4.30.0107101816580.677-100000@peter.localdomain
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In response to Re: AW: pg_index.indislossy  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: AW: pg_index.indislossy
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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@gmx.net   http://funkturm.homeip.net/~peter



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