On Mon, Aug 20, 2012 at 10:29 AM, Steven Schlansker <steven@xxxxxxxxxxxx> wrote: > > On Aug 19, 2012, at 2:37 PM, Jeff Davis <pgsql@xxxxxxxxxxx> wrote: > >> On Tue, 2012-07-10 at 00:09 -0700, Steven Schlansker wrote: >>> show that our particular application is faster by quite a bit when a >>> hash index is available. >> >> Can you publish the results somewhere? It might provoke some interest. > > I might be able to spend some time looking at making this public, but the general parameters are: > > 122M rows, lookup key is a UUID type. Lookups are ~1000 random keys at a time (as in, a giant SELECT * FROM table WHERE key IN (?,?,?,?,…) How well cached is the data? If it has to be read from disk, then a bitmap index scan on a btree index with effective_io_concurrency set high might do quite well, assuming you can convince the planner to use one. Cheers, Jeff -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
