Hash indexes (was: On-disk bitmap index patch)

On Jul 25, 2006, at 3:31 PM, Tom Lane wrote:
> Hannu Krosing <hannu@skype.net> writes:
>> Ühel kenal päeval, T, 2006-07-25 kell 13:06, kirjutas Tom Lane:
>>> The reason I have such high sales resistance is that we've
>>> carried the
>>> hash and rtree AMs for years, hoping that someone would do the
>>> work to
>>> make them actually worth using, with little result.
>
>> What would be the use-case for hash indexes ? And what should be
>> done to
>> make them faster than btree ?
>
> If we knew, we'd do it ;-)  But no one's put enough effort into it
> to find out.

Do they use the same hash algorithm as hash joins/aggregation? If so,
wouldn't hash indexes be faster for those operations than regular
indexes?
--
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
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