The following bug has been logged online: Bug reference: 5113 Logged by: dan Email address: dan.boe...@roost.com PostgreSQL version: 8.4.1 Operating system: redhat 5.3 Description: Postgres not scanning indexes Details:
Let's say I have a table t with 5 columns c1 NOT NULL, c2 NOT NULL, c3, c4, c5 and I have a UNIQUE index on (c1, c2) (remember c1 and c2 have a not null constraint) When I run the query: select c1,c2 from t I expect the explain to say index scan; instead it says table scan. The index has ALL the info I need and in my case is about 2% the size of the table. Why is Postgres still choosing to do a full table scan? The same applies to a primary key - if (c1, c2) is the primary key then I expect: select c1,c2 from t to scan only the index - instead it scans the table -- Sent via pgsql-bugs mailing list (pgsql-bugs@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-bugs
