fix-merge-bug.patch
text/x-patch
Filename: fix-merge-bug.patch
Type: text/x-patch
Part: 0
Patch
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API reference →
Format: unified
| File | + | − |
|---|---|---|
| src/backend/commands/trigger.c | 48 | 26 |
| src/backend/executor/execReplication.c | 2 | 2 |
| src/backend/executor/nodeModifyTable.c | 4 | 2 |
| src/include/commands/trigger.h | 4 | 2 |
| src/test/isolation/expected/merge-match-recheck.out | 18 | 9 |
| src/test/isolation/specs/merge-match-recheck.spec | 13 | 9 |
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c
new file mode 100644
index 67f8e70..7dc121f
--- a/src/backend/commands/trigger.c
+++ b/src/backend/commands/trigger.c
@@ -80,6 +80,7 @@ static bool GetTupleForTrigger(EState *e
ItemPointer tid,
LockTupleMode lockmode,
TupleTableSlot *oldslot,
+ bool do_epq_recheck,
TupleTableSlot **epqslot,
TM_Result *tmresultp,
TM_FailureData *tmfdp);
@@ -2693,7 +2694,8 @@ ExecBRDeleteTriggers(EState *estate, EPQ
HeapTuple fdw_trigtuple,
TupleTableSlot **epqslot,
TM_Result *tmresult,
- TM_FailureData *tmfd)
+ TM_FailureData *tmfd,
+ bool is_merge_delete)
{
TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo);
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
@@ -2708,9 +2710,17 @@ ExecBRDeleteTriggers(EState *estate, EPQ
{
TupleTableSlot *epqslot_candidate = NULL;
+ /*
+ * Get a copy of the on-disk tuple we are planning to delete. In
+ * general, if the tuple has been concurrently updated, we should
+ * recheck it using EPQ. However, if this is a MERGE DELETE action,
+ * we skip this EPQ recheck and leave it to the caller (it must do
+ * additional rechecking, and might end up executing a different
+ * action entirely).
+ */
if (!GetTupleForTrigger(estate, epqstate, relinfo, tupleid,
- LockTupleExclusive, slot, &epqslot_candidate,
- tmresult, tmfd))
+ LockTupleExclusive, slot, !is_merge_delete,
+ &epqslot_candidate, tmresult, tmfd))
return false;
/*
@@ -2800,6 +2810,7 @@ ExecARDeleteTriggers(EState *estate,
tupleid,
LockTupleExclusive,
slot,
+ false,
NULL,
NULL,
NULL);
@@ -2944,7 +2955,8 @@ ExecBRUpdateTriggers(EState *estate, EPQ
HeapTuple fdw_trigtuple,
TupleTableSlot *newslot,
TM_Result *tmresult,
- TM_FailureData *tmfd)
+ TM_FailureData *tmfd,
+ bool is_merge_update)
{
TriggerDesc *trigdesc = relinfo->ri_TrigDesc;
TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo);
@@ -2965,10 +2977,17 @@ ExecBRUpdateTriggers(EState *estate, EPQ
{
TupleTableSlot *epqslot_candidate = NULL;
- /* get a copy of the on-disk tuple we are planning to update */
+ /*
+ * Get a copy of the on-disk tuple we are planning to update. In
+ * general, if the tuple has been concurrently updated, we should
+ * recheck it using EPQ. However, if this is a MERGE UPDATE action,
+ * we skip this EPQ recheck and leave it to the caller (it must do
+ * additional rechecking, and might end up executing a different
+ * action entirely).
+ */
if (!GetTupleForTrigger(estate, epqstate, relinfo, tupleid,
- lockmode, oldslot, &epqslot_candidate,
- tmresult, tmfd))
+ lockmode, oldslot, !is_merge_update,
+ &epqslot_candidate, tmresult, tmfd))
return false; /* cancel the update action */
/*
@@ -3142,6 +3161,7 @@ ExecARUpdateTriggers(EState *estate, Res
tupleid,
LockTupleExclusive,
oldslot,
+ false,
NULL,
NULL,
NULL);
@@ -3298,6 +3318,7 @@ GetTupleForTrigger(EState *estate,
ItemPointer tid,
LockTupleMode lockmode,
TupleTableSlot *oldslot,
+ bool do_epq_recheck,
TupleTableSlot **epqslot,
TM_Result *tmresultp,
TM_FailureData *tmfdp)
@@ -3357,29 +3378,30 @@ GetTupleForTrigger(EState *estate,
if (tmfd.traversed)
{
/*
- * Recheck the tuple using EPQ. For MERGE, we leave this
- * to the caller (it must do additional rechecking, and
- * might end up executing a different action entirely).
+ * Recheck the tuple using EPQ, if requested. Otherwise,
+ * just return that it was concurrently updated.
*/
- if (estate->es_plannedstmt->commandType == CMD_MERGE)
+ if (do_epq_recheck)
{
- if (tmresultp)
- *tmresultp = TM_Updated;
- return false;
- }
-
- *epqslot = EvalPlanQual(epqstate,
- relation,
- relinfo->ri_RangeTableIndex,
- oldslot);
+ *epqslot = EvalPlanQual(epqstate,
+ relation,
+ relinfo->ri_RangeTableIndex,
+ oldslot);
- /*
- * If PlanQual failed for updated tuple - we must not
- * process this tuple!
- */
- if (TupIsNull(*epqslot))
+ /*
+ * If PlanQual failed for updated tuple - we must not
+ * process this tuple!
+ */
+ if (TupIsNull(*epqslot))
+ {
+ *epqslot = NULL;
+ return false;
+ }
+ }
+ else
{
- *epqslot = NULL;
+ if (tmresultp)
+ *tmresultp = TM_Updated;
return false;
}
}
diff --git a/src/backend/executor/execReplication.c b/src/backend/executor/execReplication.c
new file mode 100644
index 53ddd25..f262e7a
--- a/src/backend/executor/execReplication.c
+++ b/src/backend/executor/execReplication.c
@@ -670,7 +670,7 @@ ExecSimpleRelationUpdate(ResultRelInfo *
resultRelInfo->ri_TrigDesc->trig_update_before_row)
{
if (!ExecBRUpdateTriggers(estate, epqstate, resultRelInfo,
- tid, NULL, slot, NULL, NULL))
+ tid, NULL, slot, NULL, NULL, false))
skip_tuple = true; /* "do nothing" */
}
@@ -746,7 +746,7 @@ ExecSimpleRelationDelete(ResultRelInfo *
resultRelInfo->ri_TrigDesc->trig_delete_before_row)
{
skip_tuple = !ExecBRDeleteTriggers(estate, epqstate, resultRelInfo,
- tid, NULL, NULL, NULL, NULL);
+ tid, NULL, NULL, NULL, NULL, false);
}
if (!skip_tuple)
diff --git a/src/backend/executor/nodeModifyTable.c b/src/backend/executor/nodeModifyTable.c
new file mode 100644
index 54da8e7..7c6c2c1
--- a/src/backend/executor/nodeModifyTable.c
+++ b/src/backend/executor/nodeModifyTable.c
@@ -1474,7 +1474,8 @@ ExecDeletePrologue(ModifyTableContext *c
return ExecBRDeleteTriggers(context->estate, context->epqstate,
resultRelInfo, tupleid, oldtuple,
- epqreturnslot, result, &context->tmfd);
+ epqreturnslot, result, &context->tmfd,
+ context->mtstate->operation == CMD_MERGE);
}
return true;
@@ -2117,7 +2118,8 @@ ExecUpdatePrologue(ModifyTableContext *c
return ExecBRUpdateTriggers(context->estate, context->epqstate,
resultRelInfo, tupleid, oldtuple, slot,
- result, &context->tmfd);
+ result, &context->tmfd,
+ context->mtstate->operation == CMD_MERGE);
}
return true;
diff --git a/src/include/commands/trigger.h b/src/include/commands/trigger.h
new file mode 100644
index 2ed2c4b..cfd7daa
--- a/src/include/commands/trigger.h
+++ b/src/include/commands/trigger.h
@@ -213,7 +213,8 @@ extern bool ExecBRDeleteTriggers(EState
HeapTuple fdw_trigtuple,
TupleTableSlot **epqslot,
TM_Result *tmresult,
- TM_FailureData *tmfd);
+ TM_FailureData *tmfd,
+ bool is_merge_delete);
extern void ExecARDeleteTriggers(EState *estate,
ResultRelInfo *relinfo,
ItemPointer tupleid,
@@ -235,7 +236,8 @@ extern bool ExecBRUpdateTriggers(EState
HeapTuple fdw_trigtuple,
TupleTableSlot *newslot,
TM_Result *tmresult,
- TM_FailureData *tmfd);
+ TM_FailureData *tmfd,
+ bool is_merge_update);
extern void ExecARUpdateTriggers(EState *estate,
ResultRelInfo *relinfo,
ResultRelInfo *src_partinfo,
diff --git a/src/test/isolation/expected/merge-match-recheck.out b/src/test/isolation/expected/merge-match-recheck.out
new file mode 100644
index 9a44a59..90300f1
--- a/src/test/isolation/expected/merge-match-recheck.out
+++ b/src/test/isolation/expected/merge-match-recheck.out
@@ -241,19 +241,28 @@ starting permutation: update_bal1_tg mer
s2: NOTICE: Update: (1,160,s1,setup) -> (1,50,s1,"setup updated by update_bal1_tg")
step update_bal1_tg: UPDATE target_tg t SET balance = 50, val = t.val || ' updated by update_bal1_tg' WHERE t.key = 1;
step merge_bal_tg:
- MERGE INTO target_tg t
- USING (SELECT 1 as key) s
- ON s.key = t.key
- WHEN MATCHED AND balance < 100 THEN
- UPDATE SET balance = balance * 2, val = t.val || ' when1'
- WHEN MATCHED AND balance < 200 THEN
- UPDATE SET balance = balance * 4, val = t.val || ' when2'
- WHEN MATCHED AND balance < 300 THEN
- UPDATE SET balance = balance * 8, val = t.val || ' when3';
+ WITH t AS (
+ MERGE INTO target_tg t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND balance < 100 THEN
+ UPDATE SET balance = balance * 2, val = t.val || ' when1'
+ WHEN MATCHED AND balance < 200 THEN
+ UPDATE SET balance = balance * 4, val = t.val || ' when2'
+ WHEN MATCHED AND balance < 300 THEN
+ UPDATE SET balance = balance * 8, val = t.val || ' when3'
+ RETURNING t.*
+ )
+ SELECT * FROM t;
<waiting ...>
step c2: COMMIT;
s1: NOTICE: Update: (1,50,s1,"setup updated by update_bal1_tg") -> (1,100,s1,"setup updated by update_bal1_tg when1")
step merge_bal_tg: <... completed>
+key|balance|status|val
+---+-------+------+-------------------------------------
+ 1| 100|s1 |setup updated by update_bal1_tg when1
+(1 row)
+
step select1_tg: SELECT * FROM target_tg;
key|balance|status|val
---+-------+------+-------------------------------------
diff --git a/src/test/isolation/specs/merge-match-recheck.spec b/src/test/isolation/specs/merge-match-recheck.spec
new file mode 100644
index 26266b8..15226e4
--- a/src/test/isolation/specs/merge-match-recheck.spec
+++ b/src/test/isolation/specs/merge-match-recheck.spec
@@ -99,15 +99,19 @@ step "merge_bal_pa"
}
step "merge_bal_tg"
{
- MERGE INTO target_tg t
- USING (SELECT 1 as key) s
- ON s.key = t.key
- WHEN MATCHED AND balance < 100 THEN
- UPDATE SET balance = balance * 2, val = t.val || ' when1'
- WHEN MATCHED AND balance < 200 THEN
- UPDATE SET balance = balance * 4, val = t.val || ' when2'
- WHEN MATCHED AND balance < 300 THEN
- UPDATE SET balance = balance * 8, val = t.val || ' when3';
+ WITH t AS (
+ MERGE INTO target_tg t
+ USING (SELECT 1 as key) s
+ ON s.key = t.key
+ WHEN MATCHED AND balance < 100 THEN
+ UPDATE SET balance = balance * 2, val = t.val || ' when1'
+ WHEN MATCHED AND balance < 200 THEN
+ UPDATE SET balance = balance * 4, val = t.val || ' when2'
+ WHEN MATCHED AND balance < 300 THEN
+ UPDATE SET balance = balance * 8, val = t.val || ' when3'
+ RETURNING t.*
+ )
+ SELECT * FROM t;
}
step "merge_delete"