Date: Mon, 24 Jul 2006 07:21:33 +1000 (EST)
From: Gavin Sherry <swm@linuxworld.com.au>
To: Jie Zhang <jzhang@greenplum.com>
cc: pgsql-hackers@postgresql.org
Subject: Re: On-disk bitmap index patch
In-Reply-To: <C0E1CD9D.8DC0%jzhang@greenplum.com>
Message-ID: <Pine.LNX.4.58.0607240720180.19004@linuxworld.com.au>
References: <C0E1CD9D.8DC0%jzhang@greenplum.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Mon, 17 Jul 2006, Jie Zhang wrote:

> Hi,
>
> I have posted a patch to the CVS head for on-disk bitmap index to
> pgsql-patches. If this can get in 8.2, that would be great. Any comments and
> suggestions are welcome.
>
> I still need to add several items:
>
> (1) README file in src/backend/access/bitmap.
> (2) Bitmap index documentation.
> (3) Hiding the internal btree.
>
> Also, I have disabled the multi-column index support because there is a
> known problem. Assume that there is a bitmap index on a and b. When a query
> predicate has only a, the current code may generate a wrong result. That's
> because the current code assumes that b is null. The ultimate problem is
> because the search code only handles one bitmap vector now. I need a fix to
> support manipulating multiple bitmap vectors.
>
> If you find any other problems, please let me know.

Is anyone else looking at this patch? I am reviewing it with Jie, tidying
it up and trying to solve some of the problems mentioned above. If anyone
wants to take a look at us, please ask for an updated patch.

Thanks,

Gavin