On Sun, Aug 6, 2017 at 10:56 PM, Amit Langote <langote_amit...@lab.ntt.co.jp> wrote: > Good catch. I agree that getting an Append node after that commit is > unintentional and we should fix so that we don't get an Append. So, +1 to > your patch. I looked at the patch and the code fix seems to do what we want.
So, I also agree that this is a good fix, but I don't think it fixes the whole problem. Consider: rhaas=# create table parent (a int) partition by list (a); CREATE TABLE rhaas=# create temp table child partition of parent for values in (1); CREATE TABLE rhaas=# explain verbose select * from parent; QUERY PLAN ------------------------------------------------------------------------- Append (cost=0.00..35.50 rows=2550 width=4) -> Seq Scan on pg_temp_3.child (cost=0.00..35.50 rows=2550 width=4) Output: child.a (3 rows) But the comments say: * A childless table is never considered to be an inheritance set; therefore * a parent RTE must always have at least two associated AppendRelInfos. Yet, not. So at least the comments need to be updated; not sure if we want to try to eliminate the Append node in this case also. -- 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