Add hypertable support for transition table

This adds support for using statement-level triggers with transition
tables to hypertables. We deliberately do not support statement-level
nor row-level triggers with transition tables on chunks and error out
if attempts are made to either add such triggers to a chunk or create a
hypertable from a table with such triggers.

We also change the error messages to look more like the corresponding
PostgreSQL error message.

Co-Authored-By: James Sewell <jsewell@timescale.com>

.unreleased/pr_6901

@@ -0,0 +1 @@
+Implements: #6901 Add hypertable support for transition tables

src/copy.c

@@ -698,6 +698,7 @@ copyfrom(CopyChunkState *ccstate, ParseState *pstate, Hypertable *ht, MemoryCont
 	uint64 processed = 0;
 	bool has_before_insert_row_trig;
 	bool has_instead_insert_row_trig;
+	bool has_after_insert_statement_trig;
 	ExprState *qualexpr = NULL;
 	ChunkDispatch *dispatch = ccstate->dispatch;
 
@@ -808,6 +809,19 @@ copyfrom(CopyChunkState *ccstate, ParseState *pstate, Hypertable *ht, MemoryCont
 	/* Prepare to catch AFTER triggers. */
 	AfterTriggerBeginQuery();
 
+	/*
+	 * If there are any triggers with transition tables on the named relation,
+	 * we need to be prepared to capture transition tuples. Note that
+	 * ccstate->cstate is null when we migrate from an existing table in a
+	 * call from create_hypertable(), so we do not need a transition capture
+	 * state in this case.
+	 */
+	if (ccstate->cstate)
+		ccstate->cstate->transition_capture =
+			MakeTransitionCaptureState(ccstate->rel->trigdesc,
+									   RelationGetRelid(ccstate->rel),
+									   CMD_INSERT);
+
 	if (ccstate->where_clause)
 		qualexpr = ExecInitQual(castNode(List, ccstate->where_clause), NULL);
 
@@ -848,8 +862,12 @@ copyfrom(CopyChunkState *ccstate, ParseState *pstate, Hypertable *ht, MemoryCont
 	has_instead_insert_row_trig =
 		(resultRelInfo->ri_TrigDesc && resultRelInfo->ri_TrigDesc->trig_insert_instead_row);
 
+	has_after_insert_statement_trig =
+		(resultRelInfo->ri_TrigDesc && resultRelInfo->ri_TrigDesc->trig_insert_new_table);
+
 	/* Depending on the configured trigger, enable or disable the multi-insert buffers */
-	if (has_before_insert_row_trig || has_instead_insert_row_trig)
+	if (has_after_insert_statement_trig || has_before_insert_row_trig ||
+		has_instead_insert_row_trig)
 	{
 		insertMethod = CIM_SINGLE;
 		ereport(DEBUG1,
@@ -1043,12 +1061,15 @@ copyfrom(CopyChunkState *ccstate, ParseState *pstate, Hypertable *ht, MemoryCont
 																 NULL,
 																 NIL,
 																 false);
-				/* AFTER ROW INSERT Triggers */
-				ExecARInsertTriggers(estate,
-									 resultRelInfo,
-									 myslot,
-									 recheckIndexes,
-									 NULL /* transition capture */);
+				/* AFTER ROW INSERT Triggers. We do not need to do this if we
+				 * are migrating data from an existing table in a call from
+				 * create_hypertable(). */
+				if (ccstate->cstate)
+					ExecARInsertTriggers(estate,
+										 resultRelInfo,
+										 myslot,
+										 recheckIndexes,
+										 ccstate->cstate->transition_capture);
 			}
 			else
 			{
@@ -1105,8 +1126,15 @@ copyfrom(CopyChunkState *ccstate, ParseState *pstate, Hypertable *ht, MemoryCont
 
 	MemoryContextSwitchTo(oldcontext);
 
-	/* Execute AFTER STATEMENT insertion triggers */
-	ExecASInsertTriggers(estate, resultRelInfo, NULL);
+	/*
+	 * Execute AFTER STATEMENT insertion triggers.
+	 *
+	 * We do not need to do this ccstate->cstate is NULL, which is the case
+	 * when migrating data from an existing table in a call from
+	 * create_hypertable().
+	 */
+	if (ccstate->cstate)
+		ExecASInsertTriggers(estate, resultRelInfo, ccstate->cstate->transition_capture);
 
 	/* Handle queued AFTER triggers */
 	AfterTriggerEndQuery(estate);

src/hypertable.c

@@ -1925,13 +1925,10 @@ ts_hypertable_create_from_info(Oid table_relid, int32 hypertable_id, uint32 flag
 		hypertable_create_schema(NameStr(*associated_schema_name));
 
 	/*
-	 * Hypertables do not support transition tables in triggers, so if the
-	 * table already has such triggers we bail out
+	 * Hypertables do not support arbitrary triggers, so if the table already
+	 * has unsupported triggers we bail out
 	 */
-	if (ts_relation_has_transition_table_trigger(table_relid))
-		ereport(ERROR,
-				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("hypertables do not support transition tables in triggers")));
+	ts_check_unsupported_triggers(table_relid);
 
 	if (NULL == chunk_sizing_info)
 		chunk_sizing_info = ts_chunk_sizing_info_get_default_disabled(table_relid);

src/planner/planner.c

@@ -12,6 +12,7 @@
 #include <miscadmin.h>
 #include <nodes/makefuncs.h>
 #include <nodes/nodeFuncs.h>
+#include <nodes/parsenodes.h>
 #include <nodes/plannodes.h>
 #include <optimizer/appendinfo.h>
 #include <optimizer/clauses.h>
@@ -1272,8 +1273,15 @@ timescaledb_set_rel_pathlist(PlannerInfo *root, RelOptInfo *rel, Index rti, Rang
 	TsRelType reltype;
 	Hypertable *ht;
 
-	/* Quick exit if this is a relation we're not interested in */
-	if (!valid_hook_call() || !OidIsValid(rte->relid) || IS_DUMMY_REL(rel))
+	/*
+	 * Quick exit if this is a relation we're not interested in.
+	 *
+	 * If the rtekind is a named tuple store, it is a named tuple store *for*
+	 * the relation rte->relid (e.g., a transition table for a trigger), but
+	 * not the relation itself.
+	 */
+	if (!valid_hook_call() || rte->rtekind == RTE_NAMEDTUPLESTORE || !OidIsValid(rte->relid) ||
+		IS_DUMMY_REL(rel))
 	{
 		if (prev_set_rel_pathlist_hook != NULL)
 			(*prev_set_rel_pathlist_hook)(root, rel, rti, rte);

src/process_utility.c

@@ -4440,6 +4440,13 @@ process_create_trigger_start(ProcessUtilityArgs *args)
 	Hypertable *ht;
 	ObjectAddress PG_USED_FOR_ASSERTS_ONLY address;
 	Oid relid = RangeVarGetRelid(stmt->relation, NoLock, true);
+	int16 tgtype;
+
+	TRIGGER_CLEAR_TYPE(tgtype);
+	if (stmt->row)
+		TRIGGER_SETT_ROW(tgtype);
+	tgtype |= stmt->timing;
+	tgtype |= stmt->events;
 
 	hcache = ts_hypertable_cache_pin();
 	ht = ts_hypertable_cache_get_entry(hcache, relid, CACHE_FLAG_MISSING_OK);
@@ -4456,21 +4463,31 @@ process_create_trigger_start(ProcessUtilityArgs *args)
 			if (ts_chunk_get_by_relid(relid, false) != NULL)
 				ereport(ERROR,
 						(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-						 errmsg(
-							 "trigger with transition tables not supported on hypertable chunks")));
+						 errmsg("triggers with transition tables are not supported on "
+								"hypertable chunks")));
 		return DDL_CONTINUE;
 	}
 
-	if (stmt->transitionRels)
+	/*
+	 * We do not support ROW triggers with transition tables on hypertables
+	 * since these are not supported on inheritance children, and we use
+	 * inheritance for our chunks (it is actually not supported for
+	 * declarative partition tables either).
+	 */
+	if (stmt->transitionRels && TRIGGER_FOR_ROW(tgtype))
 	{
 		ts_cache_release(hcache);
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("trigger with transition tables not supported on hypertables")));
+				 errmsg("ROW triggers with transition tables are not supported on hypertables")));
 	}
 
 	add_hypertable_to_process_args(args, ht);
 
+	/*
+	 * If it is not a ROW trigger, we do not need to create the ROW triggers
+	 * on the chunks, so we can return early.
+	 */
 	if (!stmt->row)
 	{
 		ts_cache_release(hcache);

src/trigger.c

@@ -110,11 +110,13 @@ create_trigger_handler(const Trigger *trigger, void *arg)
 {
 	const Chunk *chunk = arg;
 
-	if (TRIGGER_USES_TRANSITION_TABLE(trigger->tgnewtable) ||
-		TRIGGER_USES_TRANSITION_TABLE(trigger->tgoldtable))
+	if ((TRIGGER_USES_TRANSITION_TABLE(trigger->tgoldtable) ||
+		 TRIGGER_USES_TRANSITION_TABLE(trigger->tgnewtable)) &&
+		TRIGGER_FOR_ROW(trigger->tgtype))
 		ereport(ERROR,
 				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
-				 errmsg("hypertables do not support transition tables in triggers")));
+				 errmsg("ROW triggers with transition tables are not supported on hypertable "
+						"chunks")));
 
 	if (trigger_is_chunk_trigger(trigger))
 		ts_trigger_create_on_chunk(trigger->tgoid,
@@ -164,24 +166,21 @@ ts_trigger_create_all_on_chunk(const Chunk *chunk)
 static bool
 check_for_transition_table(const Trigger *trigger, void *arg)
 {
-	bool *found = arg;
-
-	if (TRIGGER_USES_TRANSITION_TABLE(trigger->tgnewtable) ||
-		TRIGGER_USES_TRANSITION_TABLE(trigger->tgoldtable))
+	if ((TRIGGER_USES_TRANSITION_TABLE(trigger->tgnewtable) ||
+		 TRIGGER_USES_TRANSITION_TABLE(trigger->tgoldtable)) &&
+		TRIGGER_FOR_ROW(trigger->tgtype))
 	{
-		*found = true;
+		ereport(ERROR,
+				(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+				 errmsg("ROW triggers with transition tables are not supported on hypertables")));
 		return false;
 	}
 
 	return true;
 }
 
-bool
-ts_relation_has_transition_table_trigger(Oid relid)
+void
+ts_check_unsupported_triggers(Oid relid)
 {
-	bool found = false;
-
-	for_each_trigger(relid, check_for_transition_table, &found);
-
-	return found;
+	for_each_trigger(relid, check_for_transition_table, NULL);
 }

src/trigger.h

@@ -17,4 +17,4 @@
 extern void ts_trigger_create_on_chunk(Oid trigger_oid, const char *chunk_schema_name,
 									   const char *chunk_table_name);
 extern TSDLLEXPORT void ts_trigger_create_all_on_chunk(const Chunk *chunk);
-extern bool ts_relation_has_transition_table_trigger(Oid relid);
+extern void ts_check_unsupported_triggers(Oid relid);

test/expected/triggers.out

@@ -416,12 +416,15 @@ DROP TABLE location;
 -- test triggers with transition tables
 -- test creating hypertable from table with triggers with transition tables
 CREATE TABLE transition_test(time timestamptz NOT NULL);
-CREATE TRIGGER t1 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t1_stmt AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t1_row AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+-- We do not support ROW triggers with transition tables, so we need
+-- to remove it to be able to create the hypertable.
 \set ON_ERROR_STOP 0
 SELECT create_hypertable('transition_test','time');
-ERROR:  hypertables do not support transition tables in triggers
+ERROR:  ROW triggers with transition tables are not supported on hypertables
 \set ON_ERROR_STOP 1
-DROP TRIGGER t1 ON transition_test;
+DROP TRIGGER t1_row ON transition_test;
 SELECT create_hypertable('transition_test','time');
       create_hypertable       
 ------------------------------
@@ -430,27 +433,30 @@ SELECT create_hypertable('transition_test','time');
 
 -- Insert some rows to create a chunk
 INSERT INTO transition_test values ('2020-01-10');
+WARNING:  FIRING trigger when: AFTER level: STATEMENT op: INSERT cnt: 0 trigger_name t1_stmt
 SELECT chunk FROM show_chunks('transition_test') tbl(chunk) limit 1 \gset
 -- test creating trigger with transition tables on existing hypertable
-\set ON_ERROR_STOP 0
-CREATE TRIGGER t2 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertables
 CREATE TRIGGER t3 AFTER UPDATE ON transition_test REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertables
 CREATE TRIGGER t4 AFTER DELETE ON transition_test REFERENCING OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertables
-CREATE TRIGGER t2 AFTER INSERT ON :chunk REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertable chunks
+INSERT INTO transition_test values ('2020-01-11');
+WARNING:  FIRING trigger when: AFTER level: STATEMENT op: INSERT cnt: 0 trigger_name t1_stmt
+COPY transition_test FROM STDIN;
+WARNING:  FIRING trigger when: AFTER level: STATEMENT op: INSERT cnt: 0 trigger_name t1_stmt
+UPDATE transition_test SET time = '2020-01-12' WHERE time = '2020-01-11';
+WARNING:  FIRING trigger when: AFTER level: STATEMENT op: UPDATE cnt: 0 trigger_name t3
+DELETE FROM transition_test WHERE time = '2020-01-12';
+WARNING:  FIRING trigger when: AFTER level: STATEMENT op: DELETE cnt: 0 trigger_name t4
+\set ON_ERROR_STOP 0
 CREATE TRIGGER t3 AFTER UPDATE ON :chunk REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertable chunks
+ERROR:  triggers with transition tables are not supported on hypertable chunks
 CREATE TRIGGER t4 AFTER DELETE ON :chunk REFERENCING OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertable chunks
-CREATE TRIGGER t2 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertables
-CREATE TRIGGER t3 AFTER UPDATE ON transition_test REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertables
-CREATE TRIGGER t4 AFTER DELETE ON transition_test REFERENCING OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
-ERROR:  trigger with transition tables not supported on hypertables
+ERROR:  triggers with transition tables are not supported on hypertable chunks
+CREATE TRIGGER t5 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+ERROR:  ROW triggers with transition tables are not supported on hypertables
+CREATE TRIGGER t6 AFTER UPDATE ON transition_test REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+ERROR:  ROW triggers with transition tables are not supported on hypertables
+CREATE TRIGGER t7 AFTER DELETE ON transition_test REFERENCING OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+ERROR:  ROW triggers with transition tables are not supported on hypertables
 -- Test insert blocker trigger does not crash when called directly
 SELECT _timescaledb_functions.insert_blocker();
 ERROR:  insert_blocker: not called by trigger manager

test/sql/triggers.sql

@@ -305,30 +305,38 @@ DROP TABLE location;
 -- test triggers with transition tables
 -- test creating hypertable from table with triggers with transition tables
 CREATE TABLE transition_test(time timestamptz NOT NULL);
-CREATE TRIGGER t1 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t1_stmt AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t1_row AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
 
+-- We do not support ROW triggers with transition tables, so we need
+-- to remove it to be able to create the hypertable.
 \set ON_ERROR_STOP 0
 SELECT create_hypertable('transition_test','time');
 \set ON_ERROR_STOP 1
-DROP TRIGGER t1 ON transition_test;
+DROP TRIGGER t1_row ON transition_test;
 SELECT create_hypertable('transition_test','time');
 
 -- Insert some rows to create a chunk
 INSERT INTO transition_test values ('2020-01-10');
 SELECT chunk FROM show_chunks('transition_test') tbl(chunk) limit 1 \gset
 
 -- test creating trigger with transition tables on existing hypertable
-\set ON_ERROR_STOP 0
-CREATE TRIGGER t2 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
 CREATE TRIGGER t3 AFTER UPDATE ON transition_test REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
 CREATE TRIGGER t4 AFTER DELETE ON transition_test REFERENCING OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-CREATE TRIGGER t2 AFTER INSERT ON :chunk REFERENCING NEW TABLE AS new_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
+
+INSERT INTO transition_test values ('2020-01-11');
+COPY transition_test FROM STDIN;
+2020-01-09
+\.
+UPDATE transition_test SET time = '2020-01-12' WHERE time = '2020-01-11';
+DELETE FROM transition_test WHERE time = '2020-01-12';
+
+\set ON_ERROR_STOP 0
 CREATE TRIGGER t3 AFTER UPDATE ON :chunk REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
 CREATE TRIGGER t4 AFTER DELETE ON :chunk REFERENCING OLD TABLE AS old_trans FOR EACH STATEMENT EXECUTE FUNCTION test_trigger();
-
-CREATE TRIGGER t2 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
-CREATE TRIGGER t3 AFTER UPDATE ON transition_test REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
-CREATE TRIGGER t4 AFTER DELETE ON transition_test REFERENCING OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t5 AFTER INSERT ON transition_test REFERENCING NEW TABLE AS new_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t6 AFTER UPDATE ON transition_test REFERENCING NEW TABLE AS new_trans OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
+CREATE TRIGGER t7 AFTER DELETE ON transition_test REFERENCING OLD TABLE AS old_trans FOR EACH ROW EXECUTE FUNCTION test_trigger();
 
 -- Test insert blocker trigger does not crash when called directly
 SELECT _timescaledb_functions.insert_blocker();