> Thanks for your response. I tried doing what you suggested so that table now has a primary key of ' CONSTRAINT data_area_pkey PRIMARY KEY(area_id , data_id ); ' and I've added the INDEX > of 'CREATE INDEX data_area_data_id_index ON data_area USING btree (data_id );' unfortunately it hasn't resulted in an improvement of the query performance. Here is the explain > ... Did you run analyze on the table after creating the index ? GW -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
