On 14 September 2011 00:04, Stefan Keller <sfkeller@xxxxxxxxx> wrote: > Has this been verified on a recent release? I can't believe that hash > performs so bad over all these points. Theory tells me otherwise and > http://en.wikipedia.org/wiki/Hash_table seems to be a success. Hash indexes have been improved since 2005 - their performance was improved quite a bit in 9.0. Here's a more recent analysis: http://www.depesz.com/index.php/2010/06/28/should-you-use-hash-index/ -- Peter Geoghegan http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training and Services -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance