From: Ivan Voras <ivoras@fer.hr>
To: pgsql-performance@postgresql.org
Subject: Bitmasks
Date: Sat, 10 Dec 2005 18:12:58 +0100
Message-ID: <439B0C9A.6010109@fer.hr> (raw)
Can indexes be used for bit-filtering queries? For example:
create table tt (
flags integer not null default 0,
str varchar
);
select * from tt where (flags & 16) != 0;
I suspected radix trees could be used for this but it seems it doesn't
work that way.
If not, is there a way of quickly filtering by such "elements of a set"
that doesn't involve creating 32 boolean fields (which would also need
to be pretty uselessly indexed separately)?
Would strings and regular expressions work?
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To: pgsql-performance@postgresql.org
Cc: ivoras@fer.hr
Subject: Re: Bitmasks
In-Reply-To: <439B0C9A.6010109@fer.hr>
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