On Wed, Apr 13, 2016 at 11:21 PM, Etsuro Fujita <fujita.ets...@lab.ntt.co.jp> wrote: >>> 2. When a join is pushed down, deparse system columns using something >>> like "CASE WHEN r1.* IS NOT NULL THEN 0 END", except for the table OID >>> column, which gets deparsed with the table OID in place of 0. This >>> delivers the correct behavior in the presence of outer joins. >> I think that that would cause useless data transfer for such culumns. >> Why not set values locally for such columns?
Because that doesn't work properly when there are outer joins involved. I see no other way of doing that correctly that's anywhere near as simple as this. -- 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
