Re: Indexing a boolean

Renney Thomas wrote:
> scott.marlowe wrote:
>
> >On Thu, 21 Aug 2003, Kris Kiger wrote:
> >
> >
> >>I would appreciate it if I could get some thoughts on indexing a field
> >>with only two values? For example, I have a table with a few million
> >>
>
> >>Often the best approach here is to make a partial index:
> >>
> >>create index table_dx on table (bool_field) where bool_field IS TRUE;
> >>
> >>This works well if you have a large portion of the boolean fields set to
> >>FALSE, and want to find the few that are TRUE. Reverse the TRUE and false
> >>for other situations.
> >>
> >>
> >>
>
> When will PGSql have bitmapped indexes for these cases - like Oracle?
> Will it be in a release sometime soon?

Uh, we really don't know --- when someone codes it. We do have
/contrib/intarray, which might help.

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