Jack Douglas wrote: > > in 9.4, GIN indexes are pretty close to this already > > Do I understand correctly that BRIN indexes will be even closer to this? >
Yeah, in a way. You could say they are closer from the opposite end. There is one index tuple in a BRIN index for each page range (contiguous set of pages); each index tuple contains a "summary" of what in that page range. There are no exact entries. If the values are randomly scattered, the index is useless; all page ranges will have to be scanned for possibly matching tuples. If the values are perfectly clustered, the index is optimal because you scan the minimal set of pages. -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-general mailing list (pgsql-general@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
