Re: bitmapscan test, no success, again

From: Pavel Stehule <stehule(at)kix(dot)fsv(dot)cvut(dot)cz>
To: pgsql-hackers(at)postgresql(dot)org
Subject: Re: bitmapscan test, no success, again
Date: 2005-04-26 12:05:59
Message-ID: Pine.LNX.4.44.0504261342260.1977-100000@kix.fsv.cvut.cz
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Hello,

I get success, with my hyphotetic sample on big table (100000 rec) Bitmap
index scan is really usefull.

I tested select count(*) from foo where
v IN (11,11,23,11,11,11,11,11,22,71,11)

Some notes.

1. with bitmap index scan 7.16 ms
2. without bis 165.731 ms (seq. scan) !!!!

3. list of constant contains equals values. Is possible remove it?
explain analyze select count(*) from foo
where v in (11,11,11,12)

Regards

Pavel Stehule

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