Tom Lane wrote: > Heikki Linnakangas <heikki.linnakan...@enterprisedb.com> writes: >> At the moment, amgettuple only returns pointers to heap tuples. There is >> no way to return data from the index tuples. That needs to be changed to >> support index-only scans. > > What are you going to do for index types that don't store the original > data (e.g. hash)?
They will obviously not be able to regurgitate index tuples. I have not yet decided how that's going to be signaled. In the prototype patch I have, I have hard-coded that only b-trees can do that. A new column "amcanreturntuples" column in pg_am seems like the most straightforward way. (This indexam API patch isn't bothered with that yet. It just splits index_gettuple() into two) -- Heikki Linnakangas EnterpriseDB http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers