Fix cost_rescan() to account for multi-batch hashing correctly. cost_rescan assumed that we don't need to rebuild the hash table when rescanning a hash join. However, that's currently only true for single-batch joins; for a multi-batch join we must charge full freight.
This probably has escaped notice because we'd be unlikely to put a hash join on the inside of a nestloop anyway. Nonetheless, it's wrong. Fix in HEAD, but don't backpatch for fear of destabilizing plans in stable releases. Branch ------ master Details ------- http://git.postgresql.org/pg/commitdiff/69995c3b3fd64361bb4d3938315f3e88ccc01e53 Modified Files -------------- src/backend/optimizer/path/costsize.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) -- Sent via pgsql-committers mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
