Re: increase index performance

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, 14 May 2009, Ow Mun Heng wrote:
Shouldn't BITMAP indexes come into play?

Does having one index w/ 3 parameters being better than 3 index w/ 3
different parameters be better for BITMAP index seeks?

I'll let someone correct me if I'm wrong, but using a single index that exactly covers your search is always going to be better than munging together results from several indexes, even if the planner decides to turn it into a bitmap index scan (which will be more likely in PG8.4 with effective_concurrency set).

Matthew

--
I don't want the truth. I want something I can tell parliament!
                                             -- Rt. Hon. Jim Hacker MP

--
Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-performance

[Postgresql General]     [Postgresql PHP]     [PHP Users]     [PHP Home]     [PHP on Windows]     [Kernel Newbies]     [PHP Classes]     [PHP Books]     [PHP Databases]     [Yosemite]

  Powered by Linux