Re: bitmap index and IS NULL predicate

From: "Alexander Staubo" <alex(at)purefiction(dot)net>
To: "Jason Pinnix" <pinnixjason(at)yahoo(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: bitmap index and IS NULL predicate
Date: 2007-05-15 15:22:17
Message-ID: 88daf38c0705150822r4de09d80u6cc32d76c96eee47@mail.gmail.com
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On 5/15/07, Jason Pinnix <pinnixjason(at)yahoo(dot)com> wrote:
> Does the bitmap
> index not store a bit vector for the NULL value (i.e. a bit vector that
> contains a 1 for each row with a NULL value and 0 for other rows) ?

You should be able to do this with a conditional index:

create index ... (col) where col is null;

Alexander.

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