From 7aeb6404f0aa250e75b7156d21ebe12d0ec2d1c8 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 8 Nov 2020 13:08:36 -0500 Subject: In INSERT/UPDATE, use the table's real tuple descriptor as target. This back-patches commit 20d3fe900 into the v12 and v13 branches. At the time I thought that commit was not fixing any observable bug, but Bertrand Drouvot showed otherwise: adding a dropped column to the previously-considered scenario crashes v12 and v13, unless the dropped column happens to be an integer. That is, of course, because the tupdesc we derive from the plan output tlist fails to describe the dropped column accurately, so that we'll do the wrong thing with a tuple in which that column isn't NULL. There is no bug in pre-v12 branches because they already did use the table's real tuple descriptor for any trigger-returned tuple. It seems that this set of bugs can be blamed on the changes that removed es_trig_tuple_slot, though I've not attempted to pin that down precisely. Although there's no code change needed in HEAD, update the test case to include a dropped column there too. Discussion: https://postgr.es/m/db5d97c8-f48a-51e2-7b08-b73d5434d425@amazon.com Discussion: https://postgr.es/m/16644-5da7ef98a7ac4545@postgresql.org --- src/backend/executor/nodeModifyTable.c | 22 +++++++++++++++++----- 1 file changed, 17 insertions(+), 5 deletions(-) (limited to 'src/backend/executor/nodeModifyTable.c') diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 20a4c474cc4..f450e4d80ad 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -2681,15 +2681,27 @@ ExecInitModifyTable(ModifyTable *node, EState *estate, int eflags) TupleTableSlot *junkresslot; subplan = mtstate->mt_plans[i]->plan; - if (operation == CMD_INSERT || operation == CMD_UPDATE) - ExecCheckPlanOutput(resultRelInfo->ri_RelationDesc, - subplan->targetlist); junkresslot = ExecInitExtraTupleSlot(estate, NULL, table_slot_callbacks(resultRelInfo->ri_RelationDesc)); - j = ExecInitJunkFilter(subplan->targetlist, - junkresslot); + + /* + * For an INSERT or UPDATE, the result tuple must always match + * the target table's descriptor. For a DELETE, it won't + * (indeed, there's probably no non-junk output columns). + */ + if (operation == CMD_INSERT || operation == CMD_UPDATE) + { + ExecCheckPlanOutput(resultRelInfo->ri_RelationDesc, + subplan->targetlist); + j = ExecInitJunkFilterInsertion(subplan->targetlist, + RelationGetDescr(resultRelInfo->ri_RelationDesc), + junkresslot); + } + else + j = ExecInitJunkFilter(subplan->targetlist, + junkresslot); if (operation == CMD_UPDATE || operation == CMD_DELETE) { -- cgit v1.2.3