> Thanks for your response. I tried doing what you suggested so that table now has a primary key of ' CONSTRAINT
data_area_pkeyPRIMARY KEY(area_id , data_id ); ' and I've added the INDEX > of 'CREATE INDEX data_area_data_id_index ON
data_areaUSING btree (data_id );' unfortunately it hasn't resulted in an improvement of the query performance. Here is
theexplain
> ...
Did you run analyze on the table after creating the index ?
GW