From: Dean Rasheed <dean.a.rasheed@gmail.com>
To: pgsql-committers@lists.postgresql.org
Subject: pgsql: Fix BEFORE ROW trigger handling in cross-partition MERGE update.
Date: Thu, 21 Dec 2023 12:57:59 +0000
Message-ID: <E1rGIcg-00BEX6-PU@gemulon.postgresql.org> (raw)
Fix BEFORE ROW trigger handling in cross-partition MERGE update.
Fix a bug during MERGE if a cross-partition update is attempted on a
partitioned table with a BEFORE DELETE ROW trigger that returns NULL,
to prevent the update. This would cause an error to be thrown, or an
assert failure in an assert-enabled build.
This was an oversight in 9321c79c86, which failed to properly
distinguish a DELETE prevented by a trigger from one prevented by a
concurrent update. Fix by having ExecDelete() return the TM_Result
status to ExecCrossPartitionUpdate(), so that it can distinguish the
two cases, and make ExecCrossPartitionUpdate() return the TM_Result
status to ExecUpdateAct(), so that it can return the correct status
from a concurrent update.
In addition, ensure that the command tag is correctly updated by
having ExecMergeMatched() pass canSetTag to ExecUpdateAct(), rather
than passing false, so that it updates the command tag if it does a
cross-partition update, making this code path in ExecMergeMatched()
consistent with ExecUpdate().
Per bug #18238 from Alexander Lakhin. Back-patch to v15, where MERGE
was introduced.
Dean Rasheed, reviewed by Richard Guo and Jian He.
Discussion: https://postgr.es/m/18238-2f2bdc7f720180b9%40postgresql.org
Branch
------
REL_16_STABLE
Details
-------
https://git.postgresql.org/pg/commitdiff/7f07384dc2697abb405e47a7447c6edf7e07d5f9
Modified Files
--------------
src/backend/executor/nodeModifyTable.c | 20 +++++---
src/test/regress/expected/merge.out | 91 ++++++++++++++++++++++++++++++++++
src/test/regress/sql/merge.sql | 64 ++++++++++++++++++++++++
3 files changed, 167 insertions(+), 8 deletions(-)
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-committers@postgresql.org
Cc: dean.a.rasheed@gmail.com, pgsql-committers@lists.postgresql.org
Subject: Re: pgsql: Fix BEFORE ROW trigger handling in cross-partition MERGE update.
In-Reply-To: <E1rGIcg-00BEX6-PU@gemulon.postgresql.org>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox