[GENERAL] Experiences of PostgreSQL on-disk bitmap index patch
Hi! I'm working on building a PostgreSQL based data warehouse, and I'm thus very interested in any experiences and usage of the PostgreSQL bitmap index patches (which I've found on pgsql-patches). Anyone using these patchese on production systems? Anyone know if the patches run on latest stable 8.2? Issues applying the patch to latest 8.2 source? Other experiences of the patches? If there's any PgSQL developer reading this - when can on-disk bitmap indexes be expected to be included in stable PostgreSQL versions? Thank you folks! Best regards, Christian
Re: [GENERAL] Experiences of PostgreSQL on-disk bitmap index patch
Ok. Big thanks for the information. You mentioned Bizgres, do you have any more information in that direction, or do you know who to contact regarding information on Bizgres bitmap indexes. If there is a bitmap index patch in Bizgres which can be applied to the latest stable source of PostgreSQL then I have a solution until 8.4 (which I according to your answers is the assumed release for introducing on-disk bitmap indexes). Any guess when 8.4 could be production ready? A year or more? Regards, Christian 2007/6/21, Alexander Staubo <[EMAIL PROTECTED]>: On 6/20/07, Joshua D. Drake <[EMAIL PROTECTED]> wrote: > Just so there is no confusion. These WILL NOT be in 8.3: > > http://developer.postgresql.org/index.php/Todo:PatchStatus Apologies. I didn't know they had been put on hold. Alexander.
Re: [GENERAL] Experiences of PostgreSQL on-disk bitmap index patch
Thanks Robert!
So you indicate that the so called bitmap index scan, a.k.a in-memory bitmap
indexes (right?), already adds such an improvement when it comes to
optimized response time on large query sets (having the characteristics as
normally used to identify cases where bitmap indexes improves performance
like: low cardinality keys, large data volumes etc), so that the on-disk
indexes are not really needed or atleast not worth wile implementing?
Regards,
Christian
2007/6/25, Robert Treat <[EMAIL PROTECTED]>:
On Thursday 21 June 2007 04:39, Christan Josefsson wrote:
> Ok.
>
> Big thanks for the information.
>
> You mentioned Bizgres, do you have any more information in that
direction,
> or do you know who to contact regarding information on Bizgres bitmap
> indexes. If there is a bitmap index patch in Bizgres which can be
applied
> to the latest stable source of PostgreSQL then I have a solution until
8.4
> (which I according to your answers is the assumed release for
introducing
> on-disk bitmap indexes).
>
If you really want to see on-disk bitmaps in, you might want to study the
patches and the missing vacuum related bits and then think about
submitting
an updated version. My take on the future of that patch is the original
developers aren't terribly motivated to finish it, in much part because
some
of the testing people have done vs. 8.3 shows it solves an even smaller
number of issues than originally hoped. my .02 anyway.
--
Robert Treat
Build A Brighter LAMP :: Linux Apache {middleware} PostgreSQL
[GENERAL] Advanced query rewrite
Hi! I was looking into the PostgreSQL RULE system in order to define rewriting / redirecting queries under certain conditions. For my part I would like to fully be able to control the query rewrite, e.g by implemening a stored procedure to define the query rewrite results, since as it seems the means of defining a SELECT RULE doesn't fullfill my requirements. Does anyone know if that would be possible? What I wan't to achieve is to implement a "agggregare (summary table) navigator" which should transparently rewrite SQL directed to certain large tables to related summary tables instead and for this the RULE system seems too limited (without being able to implement an own rewrite procedure). Any input on this matter would be much appreciated! Thanks and Regards, Christian
