On Fri, Jul 28, 2006 at 02:43:23PM -0700, Luke Lonergan wrote:
> On 7/28/06 1:25 PM, "Bruce Momjian" <bruce@momjian.us> wrote:
> > What we don't want to happen is for us to release bitmapped indexes, and
> > find out later that btree is better in all cases. Then we have to tell
> > people not to use bitmapped indexes until we fix it in the next major
> > releasse. FYI, that is basically where we are right now with hash
> > indexes.
> On this thread people have presented results that show clear and irrefutable
> evidence that there are use cases where bitmap indexes outperform Btree for
> many datatypes on realistic problems, including the TPC-H benchmark.

Irrefutable is a little optimistic, don't you think? :-)

There is reason to believe that a bitmap index is useful in some
scenarios. We're not yet clear on what these are, whether they apply
to production use scenarios, or whether b-tree could not be optimized
to be better.

I support you - I want to see these great things for myself.

But irrefutable? Irrefutable is not true. :-)

Cheers,
mark

--
mark@mielke.cc / markm@ncf.ca / markm@nortel.com __________________________
.. . _ ._ . . .__ . . ._. .__ . . . .__ | Neighbourhood Coder
|\/| |_| |_| |/ |_ |\/| | |_ | |/ |_ |
| | | | | \ | \ |__ . | | .|. |__ |__ | \ |__ | Ottawa, Ontario, Canada

One ring to rule them all, one ring to find them, one ring to bring them all
and in the darkness bind them...

http://mark.mielke.cc/


---------------------------(end of broadcast)---------------------------
TIP 5: don't forget to increase your free space map settings