=?ISO-8859-1?Q?Gunnlaugur_=DE=F3r_Briem?= <gunnlaugur@xxxxxxxxx> writes: > I did this: > CREATE VIEW unionview AS > SELECT col, otherstuff FROM (heavy subquery) > WHERE col BETWEEN 1 AND 3 > UNION ALL > SELECT col, otherstuff FROM (another heavy subquery) > WHERE col BETWEEN 4 AND 6; > hoping that the planner could use the WHERE conditions (like it would use check constraints on tables) to exclude one of the subqueries, for a query like: > SELECT * FROM unionview WHERE col=2; > But it doesn't. (In PostgreSQL 8.4.5, at least.) Works for me in 8.4.8. Do you have constraint_exclusion set to ON? regards, tom lane -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
