Fix MERGE into a plain inheritance parent table. When a MERGE's target table is the parent of an inheritance tree, any INSERT actions insert into the parent table using ModifyTableState's rootResultRelInfo. However, there are two bugs in the way this is initialized:
1. ExecInitMerge() incorrectly uses a different ResultRelInfo entry from ModifyTableState's resultRelInfo array to build the insert projection, which may not be compatible with rootResultRelInfo. 2. ExecInitModifyTable() does not fully initialize rootResultRelInfo. Specifically, ri_WithCheckOptions, ri_WithCheckOptionExprs, ri_returningList, and ri_projectReturning are not initialized. This can lead to crashes, or incorrect query results due to failing to check WCO's or process the RETURNING list for INSERT actions. Fix both these bugs in ExecInitMerge(), noting that it is only necessary to fully initialize rootResultRelInfo if the MERGE has INSERT actions and the target table is a plain inheritance parent. Backpatch to v15, where MERGE was introduced. Reported-by: Andres Freund <and...@anarazel.de> Author: Dean Rasheed <dean.a.rash...@gmail.com> Reviewed-by: Jian He <jian.universal...@gmail.com> Reviewed-by: Tender Wang <tndrw...@gmail.com> Discussion: https://postgr.es/m/4rlmjfniiyffp6b3kv4pfy4jw3pciy6mq72rdgnedsnbsx7qe5@j5hlpiwdguvc Backpatch-through: 15 Branch ------ REL_15_STABLE Details ------- https://git.postgresql.org/pg/commitdiff/d6a3f3272ffee792e27c5dd871d7cf1cbf418962 Modified Files -------------- src/backend/executor/nodeModifyTable.c | 92 ++++++++++++++++++++++++++++++++-- src/test/regress/expected/merge.out | 58 +++++++++++++++++++++ src/test/regress/sql/merge.sql | 41 +++++++++++++++ 3 files changed, 188 insertions(+), 3 deletions(-)
