Hi David, Thanks, i can see the logic there. To place a constant in front, i tried putting 'pc'||pcode in to the index and 'pc'||$1 in to the WHERE clause. It had no effect - does the planner see this as a cheat and i need to actually prefix the data in the tables? Andy -- View this message in context: http://postgresql.1045698.n5.nabble.com/expression-index-not-used-within-function-tp5778236p5778319.html Sent from the PostgreSQL - general mailing list archive at Nabble.com. -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
