Re: On-disk bitmap index patch

> -----Original Message-----
> From: pgsql-hackers-owner(at)postgresql(dot)org [mailto:pgsql-hackers-
> owner(at)postgresql(dot)org] On Behalf Of Luke Lonergan
> Sent: Friday, July 28, 2006 12:18 PM
> To: Jim C. Nasby; Jie Zhang
> Cc: Tom Lane; Mark Kirkwood; Josh Berkus; Gavin Sherry; pgsql-
> hackers(at)postgresql(dot)org
> Subject: Re: [HACKERS] On-disk bitmap index patch
>
> Jim,
>
> On 7/28/06 10:17 AM, "Jim C. Nasby" <jnasby(at)pervasive(dot)com> wrote:
>
> > If the usefulness of bitmap indexes is still in doubt, could someone
at
> > Greenplum provide data from actual data warehouses from actual
> > customers?
>
> First, is anyone in doubt?

Others have looked into the usefulness of bitmap indexes. Here is what
they found:
http://www.oracle.com/technology/pub/articles/sharma_indexes.html
http://citeseer.ist.psu.edu/stockinger02bitmap.html

Oracle, IBM, and even Microsoft[1] supports them. Probably not just to
be trendy.

[1] Microsoft SQL Server creates temporary bitmap indexes during some
queries, though you cannot declaratively create a bitmap index.

> - Luke
>
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