If the table can be clustered on that column, I suspect
it'd be a nice case for the grouped index tuples patch
http://community.enterprisedb.com/git/
Actually, simply clustering on that column might give
major speedups anyway.
Vikul Khosla wrote:
> Folks,
>
> We have just migrated from Oracle to
dexes on low cardinality columns
On Fri, Oct 16, 2009 at 4:36 PM, Vikul Khosla wrote:
> In Oracle, we replaced the B-Tree Indexes with Bitmap indexes and saw
> performance go
> through the roof. I know Postgres does not have Bitmap indexes,
> but is there a reasonable alternative to boo
On Sat, Oct 17, 2009 at 10:02 AM, Vikul Khosla wrote:
>
> Thanks Greg!.
>
> Yes, we do need to query on all 3000 values ... potentially. Considering
> that when we changed the B-Tree indexes to Bitmap indexes in Oracle
> we saw a huge performance boost ... doesn't that suggest that absence of
> th
On Sat, Oct 17, 2009 at 1:02 PM, Vikul Khosla wrote:
>
> Thanks Greg!.
>
> Yes, we do need to query on all 3000 values ... potentially. Considering
> that when we changed the B-Tree indexes to Bitmap indexes in Oracle
> we saw a huge performance boost ... doesn't that suggest that absence of
> thi
dexes on low cardinality columns
On Fri, Oct 16, 2009 at 4:36 PM, Vikul Khosla wrote:
> In Oracle, we replaced the B-Tree Indexes with Bitmap indexes and saw
> performance go
> through the roof. I know Postgres does not have Bitmap indexes,
> but is there a reasonable alternative to boo
On Fri, Oct 16, 2009 at 4:36 PM, Vikul Khosla wrote:
> In Oracle, we replaced the B-Tree Indexes with Bitmap indexes and saw
> performance go
> through the roof. I know Postgres does not have Bitmap indexes,
> but is there a reasonable alternative to boost performance in situations
> where low car
Folks,
We have just migrated from Oracle to PG.
We have a database that has approx 3 mil rows and one of the columns has a
cardinality
of only 0.1% (3000 unique values).
We have to issue several queries that use this low cardinality column in a
WHERE clause
as well as see this column particip
