From: Bruce Momjian <pgman@candle.pha.pa.us>
Message-Id: <200208221430.g7MEUdA27489@candle.pha.pa.us>
Subject: Re: BITMAP INDEXES...
In-Reply-To: <200208221352.24278.mallah@trade-india.com>
To: "Rajesh Kumar Mallah." <mallah@trade-india.com>
Date: Thu, 22 Aug 2002 10:30:39 -0400 (EDT)
Cc: pgsql-sql@postgresql.org
MIME-Version: 1.0
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See the email about bitmapped indexes linked to from the TODO list item
on bitmaps.  Bitmap indexes allow arbitrary indexes to be combined into
a single index.  Btree indexes can not be combined.

---------------------------------------------------------------------------

Rajesh Kumar Mallah. wrote:
> Hi,
> 
> I have learnt from certain texts  that bitmap indexes are very useful for
> large DSS (decesion support systems).
> 
> bitmap indexes are currently not available in postgresql.
> 
> My question is in what way is a normal btree index in pgsql
> inferior to bitmap indexes (found in oracle for example).
> 
> is it just in terms of space requirements for performance too?
> 
> 
> regds
> mallah.
> 
> 
> -- 
> Rajesh Kumar Mallah,
> Project Manager (Development)
> Infocom Network Limited, New Delhi
> phone: +91(11)6152172 (221) (L) ,9811255597 (M)
> 
> Visit http://www.trade-india.com ,
> India's Leading B2B eMarketplace.
> 
> 
> 
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