Hello there are maybe planner bug.
test case: CREATE TABLE person ( id SERIAL PRIMARY KEY, name VARCHAR(64) ) WITHOUT OIDS; CREATE TABLE person_data ( id SERIAL PRIMARY KEY ) WITHOUT OIDS; ------------------------------------ SELECT name FROM person WHERE name IN ( SELECT name FROM person p LEFT JOIN person_data ON p.id = person_data.id ) postgres=# explain SELECT name FROM person WHERE name IN ( SELECT name FROM person p LEFT JOIN person_data ON p.id = person_data.id); ERROR: failed to build any 2-way joins it works on 8.3 report by Vaclav Novotny Regards Pavel -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers