Expand partitioned tables in PartDesc order. Previously, we expanded the inheritance hierarchy in the order in which find_all_inheritors had locked the tables, but that turns out to block quite a bit of useful optimization. For example, a partition-wise join can't count on two tables with matching bounds to get expanded in the same order.
Where possible, this change results in expanding partitioned tables in *bound* order. Bound order isn't well-defined for a list-partitioned table with a null-accepting partition or for a list-partitioned table where the bounds for a single partition are interleaved with other partitions. However, when expansion in bound order is possible, it opens up further opportunities for optimization, such as strength-reducing MergeAppend to Append when the expansion order matches the desired sort order. Patch by me, with cosmetic revisions by Ashutosh Bapat. Discussion: http://postgr.es/m/CA+TgmoZrKj7kEzcMSum3aXV4eyvvbh9WD=c6m=002wmhedy...@mail.gmail.com Branch ------ master Details ------- https://git.postgresql.org/pg/commitdiff/30833ba154e0c1106d61e3270242dc5999a3e4f3 Modified Files -------------- src/backend/optimizer/prep/prepunion.c | 328 ++++++++++++++++++++++----------- src/test/regress/expected/insert.out | 4 +- 2 files changed, 220 insertions(+), 112 deletions(-) -- Sent via pgsql-committers mailing list (pgsql-committers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-committers
