On Sat, Sep 23, 2017 at 6:29 AM, Julien Rouhaud <rjuju...@gmail.com> wrote: > That's true, but numCols, sortColdIdx etc are also used to display the > sort key in an explain. If an append can return sorted data, it > should also display the sort information, so I think these fields are > still required in an Append node.
I don't think so. An index scan doesn't output that information, nor does a nested loop which inherits a sort order from its outer path. I think the rule is that a plan node which takes steps to get the data into a certain order might want to output something about that, but a plan node which somehow gets that ordering without taking any explicit action doesn't print anything. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers