Hi, we have a table partitioned by time. Each month goes into a separate child table. Primary key in each table is (underlying, ts). The resulting index is perfect for ordering like in the query below. Each child table has a constraint like: CHECK(ts>= '2011-1-1' and ts<'2011-1-1'::DATE + interval '1 month') Now, we have queries of this type: SELECT * FROM tick WHERE underlying = 'R_50' AND ts <= '2013-05-02' ORDER BY ts DESC LIMIT 100 The query plan for this is at http://explain.depesz.com/s/fB6 According to this plan it fetches all the result tuples from tick_2013_4 which is fine because tick_2013_5 obviously does not contain matches. My question is, why does it then try to fetch one row from every other index? Can that be avoided without a lower bound on ts? Thanks, Torsten -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
