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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2021-03-30 20:01:27 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2021-03-30 20:01:31 -0400 |
| commit | 65158f497a7d7523ad438b2034d01a560fafe6bd (patch) | |
| tree | de4d0b2df57bf93cbd1d26be5a6533cc7fb79a89 /src/backend/commands/trigger.c | |
| parent | 9ee7d533dacf8594057ced2d016250f09056c284 (diff) | |
| download | postgresql-65158f497a7d7523ad438b2034d01a560fafe6bd.tar.gz postgresql-65158f497a7d7523ad438b2034d01a560fafe6bd.zip | |
Remove small inefficiency in ExecARDeleteTriggers/ExecARUpdateTriggers.
Whilst poking at nodeModifyTable.c, I chanced to notice that while
its calls to ExecBR*Triggers and ExecIR*Triggers are protected by
tests to see if there are any relevant triggers to fire, its calls
to ExecAR*Triggers are not; the latter functions do the equivalent
tests themselves. This seems possibly reasonable given the more
complex conditions involved, but what's less reasonable is that
the ExecAR* functions aren't careful to do no work when there is
no work to be done. ExecARInsertTriggers gets this right, but the
other two will both force creation of a slot that the query may
have no use for. ExecARUpdateTriggers additionally performed a
usually-useless ExecClearTuple() on that slot. This is probably
all pretty microscopic in real workloads, but a cycle shaved is a
cycle earned.
Diffstat (limited to 'src/backend/commands/trigger.c')
| -rw-r--r-- | src/backend/commands/trigger.c | 10 |
1 files changed, 6 insertions, 4 deletions
diff --git a/src/backend/commands/trigger.c b/src/backend/commands/trigger.c index 7383d5994eb..0ee318b3409 100644 --- a/src/backend/commands/trigger.c +++ b/src/backend/commands/trigger.c @@ -2546,11 +2546,12 @@ ExecARDeleteTriggers(EState *estate, ResultRelInfo *relinfo, TransitionCaptureState *transition_capture) { TriggerDesc *trigdesc = relinfo->ri_TrigDesc; - TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo); if ((trigdesc && trigdesc->trig_delete_after_row) || (transition_capture && transition_capture->tcs_delete_old_table)) { + TupleTableSlot *slot = ExecGetTriggerOldSlot(estate, relinfo); + Assert(HeapTupleIsValid(fdw_trigtuple) ^ ItemPointerIsValid(tupleid)); if (fdw_trigtuple == NULL) GetTupleForTrigger(estate, @@ -2829,9 +2830,6 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo, TransitionCaptureState *transition_capture) { TriggerDesc *trigdesc = relinfo->ri_TrigDesc; - TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo); - - ExecClearTuple(oldslot); if ((trigdesc && trigdesc->trig_update_after_row) || (transition_capture && @@ -2844,6 +2842,8 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo, * separately for DELETE and INSERT to capture transition table rows. * In such case, either old tuple or new tuple can be NULL. */ + TupleTableSlot *oldslot = ExecGetTriggerOldSlot(estate, relinfo); + if (fdw_trigtuple == NULL && ItemPointerIsValid(tupleid)) GetTupleForTrigger(estate, NULL, @@ -2854,6 +2854,8 @@ ExecARUpdateTriggers(EState *estate, ResultRelInfo *relinfo, NULL); else if (fdw_trigtuple != NULL) ExecForceStoreHeapTuple(fdw_trigtuple, oldslot, false); + else + ExecClearTuple(oldslot); AfterTriggerSaveEvent(estate, relinfo, TRIGGER_EVENT_UPDATE, true, oldslot, newslot, recheckIndexes, |