On Mon, Oct 17, 2016 at 4:56 AM, Amit Kapila <amit.kapil...@gmail.com> wrote: > + node->nreaders < 2) ... > I see there are small discrepancies in both the codes like I don't see > the use of single_copy flag, as it is present in gather node.
single_copy doesn't make sense for GatherMerge, because the whole point is to merge a bunch of individually-sorted output streams into a single stream. If you have only one stream of tuples, you don't need to merge anything: you could have just used Gather for that. It does, however, make sense to merge one worker's output with the leader's output. -- 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
