Thread: doubts

sangeetha k.s wrote:
> hello,
>
>       postgresql uses bitmap indexing for indexing  in databases.
>       *Is there any technique used*
> *  used to compress the bitmap indices in postgresql*,like oracle that uses
> Byte Aligned bitmap compression to compress bitmaps.

Postgres does not support bitmap indexes yet.  What it does support is
bitmap index *scanning*.  And yes, there is a lossy compression method
that is sometimes used.

--
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.