From 37a521951ca8d290fde9913bda65e3ef5b147fe2 Mon Sep 17 00:00:00 2001 From: jian he Date: Tue, 14 Apr 2026 12:10:09 +0800 Subject: [PATCH v5] Skip FOR PORTION OF leftovers after INSTEAD OF trigger We should not try to insert temporal leftovers following an INSTEAD OF trigger. For one thing, the resultRel is the view, not the base relation, so we can't look up the pre-update/delete row. But also, the INSTEAD OF trigger is responsible for doing the work, and we don't know what it really did. If it wants leftovers, it should insert them or use FOR PORTION OF itself. Discussion: https://postgr.es/m/CAHg%2BQDd74fnd4obCRMqVS0AVWf%3DcSFH%3DCv7trTJWgm%2B_bhTK6w%40mail.gmail.com Discussion: https://postgr.es/m/CAJ7c6TME%2Bix6VRf-2TPnVTsj8qn_hy6sYAOmMhZEivwsu2wS6g%40mail.gmail.com --- doc/src/sgml/dml.sgml | 7 ++++ src/backend/executor/nodeModifyTable.c | 20 +++++++++- src/test/regress/expected/for_portion_of.out | 41 ++++++++++++++++++++ src/test/regress/sql/for_portion_of.sql | 33 ++++++++++++++++ 4 files changed, 99 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/dml.sgml b/doc/src/sgml/dml.sgml index 429aae9bd7b..4b29e675f2e 100644 --- a/doc/src/sgml/dml.sgml +++ b/doc/src/sgml/dml.sgml @@ -389,6 +389,13 @@ DELETE FROM products are not. + + If the updated table has an INSTEAD OF trigger, then + PostgreSQL skips updating the start/end times + or inserting temporal leftovers. It is the responsibility of the trigger + to make whatever changes are desired. + + When temporal leftovers are inserted, all INSERT triggers are fired, but permission checks for inserting rows are diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c index 4cb057ca4f9..8eba0ae3ecf 100644 --- a/src/backend/executor/nodeModifyTable.c +++ b/src/backend/executor/nodeModifyTable.c @@ -1826,7 +1826,15 @@ ExecDeleteEpilogue(ModifyTableContext *context, ResultRelInfo *resultRelInfo, /* Compute temporal leftovers in FOR PORTION OF */ if (((ModifyTable *) context->mtstate->ps.plan)->forPortionOf) - ExecForPortionOfLeftovers(context, estate, resultRelInfo, tupleid); + { + /* + * Skip leftovers if there were INSTEAD OF triggers. + * We would have no way of accessing the old row. + */ + if (!resultRelInfo->ri_TrigDesc || + !resultRelInfo->ri_TrigDesc->trig_delete_instead_row) + ExecForPortionOfLeftovers(context, estate, resultRelInfo, tupleid); + } /* AFTER ROW DELETE Triggers */ ExecARDeleteTriggers(estate, resultRelInfo, tupleid, oldtuple, @@ -2631,7 +2639,15 @@ ExecUpdateEpilogue(ModifyTableContext *context, UpdateContext *updateCxt, /* Compute temporal leftovers in FOR PORTION OF */ if (((ModifyTable *) context->mtstate->ps.plan)->forPortionOf) - ExecForPortionOfLeftovers(context, context->estate, resultRelInfo, tupleid); + { + /* + * Skip leftovers if there were INSTEAD OF triggers. + * We would have no way of accessing the old row. + */ + if (!resultRelInfo->ri_TrigDesc || + !resultRelInfo->ri_TrigDesc->trig_delete_instead_row) + ExecForPortionOfLeftovers(context, context->estate, resultRelInfo, tupleid); + } /* AFTER ROW UPDATE Triggers */ ExecARUpdateTriggers(context->estate, resultRelInfo, diff --git a/src/test/regress/expected/for_portion_of.out b/src/test/regress/expected/for_portion_of.out index 31f772c723d..5f296f1324e 100644 --- a/src/test/regress/expected/for_portion_of.out +++ b/src/test/regress/expected/for_portion_of.out @@ -2097,4 +2097,45 @@ SELECT * FROM temporal_partitioned_5 ORDER BY id, valid_at; (4 rows) DROP TABLE temporal_partitioned; +-- Inserting leftovers should be skipped on views with INSTEAD OF triggers +CREATE TABLE fpo_instead_base (id int, valid_at daterange, val int); +INSERT INTO fpo_instead_base VALUES (1, '[2024-01-01,2025-01-01)', 100); +CREATE VIEW fpo_instead_view AS SELECT * FROM fpo_instead_base; +CREATE FUNCTION fpo_instead_trig_fn() RETURNS trigger LANGUAGE plpgsql AS $$ +BEGIN + if TG_OP = 'UPDATE' then + raise NOTICE 'UPDATE OLD: %, NEW: %', OLD, NEW; + RETURN NEW; + elsif TG_OP = 'INSERT' then + raise NOTICE 'INSERT NEW: %', NEW; + RETURN NEW; + elsif TG_OP = 'DELETE' then + raise NOTICE 'DELETE: OLD: %', OLD; + RETURN OLD; + end if; + RETURN NEW; +END; +$$; +CREATE TRIGGER fpo_instead_trig INSTEAD OF UPDATE OR DELETE ON fpo_instead_view + FOR EACH ROW EXECUTE FUNCTION fpo_instead_trig_fn(); +UPDATE fpo_instead_view FOR PORTION OF valid_at FROM '2024-04-01' TO '2024-08-01' + SET val = 999 WHERE id = 1; +NOTICE: UPDATE OLD: (1,"[2024-01-01,2025-01-01)",100), NEW: (1,"[2024-01-01,2025-01-01)",999) +SELECT * FROM fpo_instead_view; + id | valid_at | val +----+-------------------------+----- + 1 | [2024-01-01,2025-01-01) | 100 +(1 row) + +DELETE FROM fpo_instead_view FOR PORTION OF valid_at FROM '2024-04-01' TO '2024-08-01' + WHERE id = 1; +NOTICE: DELETE: OLD: (1,"[2024-01-01,2025-01-01)",100) +SELECT * FROM fpo_instead_view; + id | valid_at | val +----+-------------------------+----- + 1 | [2024-01-01,2025-01-01) | 100 +(1 row) + +DROP VIEW fpo_instead_view; +DROP TABLE fpo_instead_base; RESET datestyle; diff --git a/src/test/regress/sql/for_portion_of.sql b/src/test/regress/sql/for_portion_of.sql index d4062acf1d1..32ea456b6a2 100644 --- a/src/test/regress/sql/for_portion_of.sql +++ b/src/test/regress/sql/for_portion_of.sql @@ -1365,4 +1365,37 @@ SELECT * FROM temporal_partitioned_5 ORDER BY id, valid_at; DROP TABLE temporal_partitioned; +-- Inserting leftovers should be skipped on views with INSTEAD OF triggers +CREATE TABLE fpo_instead_base (id int, valid_at daterange, val int); +INSERT INTO fpo_instead_base VALUES (1, '[2024-01-01,2025-01-01)', 100); +CREATE VIEW fpo_instead_view AS SELECT * FROM fpo_instead_base; +CREATE FUNCTION fpo_instead_trig_fn() RETURNS trigger LANGUAGE plpgsql AS $$ +BEGIN + if TG_OP = 'UPDATE' then + raise NOTICE 'UPDATE OLD: %, NEW: %', OLD, NEW; + RETURN NEW; + elsif TG_OP = 'INSERT' then + raise NOTICE 'INSERT NEW: %', NEW; + RETURN NEW; + elsif TG_OP = 'DELETE' then + raise NOTICE 'DELETE: OLD: %', OLD; + RETURN OLD; + end if; + RETURN NEW; +END; +$$; +CREATE TRIGGER fpo_instead_trig INSTEAD OF UPDATE OR DELETE ON fpo_instead_view + FOR EACH ROW EXECUTE FUNCTION fpo_instead_trig_fn(); + +UPDATE fpo_instead_view FOR PORTION OF valid_at FROM '2024-04-01' TO '2024-08-01' + SET val = 999 WHERE id = 1; +SELECT * FROM fpo_instead_view; + +DELETE FROM fpo_instead_view FOR PORTION OF valid_at FROM '2024-04-01' TO '2024-08-01' + WHERE id = 1; +SELECT * FROM fpo_instead_view; + +DROP VIEW fpo_instead_view; +DROP TABLE fpo_instead_base; + RESET datestyle; -- 2.47.3