On Fri, 2006-11-10 at 18:55 -0500, Tom Lane wrote:
> [ cc'ing to pgsql-performance because of performance issue for hash indexes ]
>
> "Balazs Nagy" <bnagy@thenewpush.com> writes:
> > Database table size: ~60 million rows
> > Field to index: varchar 127
>
> > CREATE INDEX ... USING hash ...
I'd be interested in a performance test that shows this is the best way
to index a table though, especially for such a large column. No wonder
there is an 8GB index.
> One thought that comes to mind is to require hash to do an smgrextend()
> addressing the last block it intends to use whenever it allocates a new
> batch of blocks, whereupon md.c could adopt a saner API: allow
> smgrextend but not other calls to address blocks beyond the current EOF.
> Thoughts?
Yes, do it.
--
Simon Riggs
EnterpriseDB http://www.enterprisedb.com