Re: Hash index use presently(?) discouraged since 2005: revive or bury it? - Mailing list pgsql-performance

On 14.09.2011 03:24, Tom Lane wrote:
> The big picture though is that we're not going to remove hash indexes,
> even if they're nearly useless in themselves, because hash index
> opclasses provide the foundation for the system's knowledge of how to
> do the datatype-specific hashing needed for hash joins and hash
> aggregation.  And those things *are* big wins, even if hash indexes
> themselves never become so.

We could drop the hash indexam code but keep the opclasses etc. I'm not
sure that would gain us, though.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com