The following bug has been logged online: Bug reference: 5542 Logged by: Roman Email address: zo...@oe-it.ru PostgreSQL version: 9.0 Operating system: Win7 x64 Description: Query optimization problem Details:
I have a query: SELECT d1.ID, d2.ID FROM DocPrimary d1 JOIN DocPrimary d2 ON d2.BasedOn=d1.ID WHERE (d1.ID=234409763) or (d2.ID=234409763) i think what QO(Query Optimizer) can make it faster (now it seq scan and on million records works 7 sec) SELECT d1.ID, d2.ID FROM DocPrimary d1 JOIN DocPrimary d2 ON d2.BasedOn=d1.ID WHERE (d2.BasedOn=234409763) or (d2.ID=234409763) Result of this query are identical (and can get by replace part of where use join dependence) And it works 0-10ms I think, what QO can undertstand it self. Table create query: CREATE TABLE docprimary ( id integer NOT NULL, basedon integer, CONSTRAINT id_pk PRIMARY KEY (id) ); CREATE INDEX basedon_idx ON docprimary USING btree (basedon); -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs