On Thu, Jun 28, 2012 at 8:16 AM, David E. Wheeler <da...@justatheory.com> wrote: > Hackers, > > Very interesting design document for SQLite 4: > > http://www.sqlite.org/src4/doc/trunk/www/design.wiki > > I'm particularly intrigued by "covering indexes". For example: > > CREATE INDEX cover1 ON table1(a,b) COVERING(c,d); > > This allows the following query to do an index-only scan: > > SELECT c, d FROM table1 WHERE a=? AND b=?; > > Now that we have index-only scans in 9.2, I'm wondering if it would make > sense to add covering index support, too, where additional, unindexed columns > are stored alongside indexed columns. > > And I wonder if it would work well with expressions, too? > > David
IRC MS SQL also allow unindexed columns in the index. -- Rob Wultsch wult...@gmail.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
