On Tue, Dec 1, 2015 at 7:53 AM, Anastasia Lubennikova <a.lubennik...@postgrespro.ru> wrote: > If we don't need c4 as an index scankey, we don't need any btree opclass on > it. > But we still want to have it in covering index for queries like > > SELECT c4 FROM tbl WHERE c1=1000; // uses the IndexOnlyScan > SELECT * FROM tbl WHERE c1=1000; // uses the IndexOnlyScan > > The patch "optional_opclass" completely ignores opclasses of included > attributes.
OK, I don't get it. Why have an opclass here at all, even optionally? -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
