diff options
Diffstat (limited to 'src/backend/commands/constraint.c')
| -rw-r--r-- | src/backend/commands/constraint.c | 17 |
1 files changed, 11 insertions, 6 deletions
diff --git a/src/backend/commands/constraint.c b/src/backend/commands/constraint.c index b0cad4634b2..f99826939c4 100644 --- a/src/backend/commands/constraint.c +++ b/src/backend/commands/constraint.c @@ -89,9 +89,10 @@ unique_key_recheck(PG_FUNCTION_ARGS) * because this trigger gets queued only in response to index insertions; * which means it does not get queued for HOT updates. The row we are * called for might now be dead, but have a live HOT child, in which case - * we still need to make the check. Therefore we have to use - * heap_hot_search, not just HeapTupleSatisfiesVisibility as is done in - * the comparable test in RI_FKey_check. + * we still need to make the check --- effectively, we're applying the + * check against the live child row, although we can use the values from + * this row since by definition all columns of interest to us are the + * same. * * This might look like just an optimization, because the index AM will * make this identical test before throwing an error. But it's actually @@ -159,7 +160,9 @@ unique_key_recheck(PG_FUNCTION_ARGS) { /* * Note: this is not a real insert; it is a check that the index entry - * that has already been inserted is unique. + * that has already been inserted is unique. Passing t_self is + * correct even if t_self is now dead, because that is the TID the + * index will know about. */ index_insert(indexRel, values, isnull, &(new_row->t_self), trigdata->tg_relation, UNIQUE_CHECK_EXISTING); @@ -168,10 +171,12 @@ unique_key_recheck(PG_FUNCTION_ARGS) { /* * For exclusion constraints we just do the normal check, but now it's - * okay to throw error. + * okay to throw error. In the HOT-update case, we must use the live + * HOT child's TID here, else check_exclusion_constraint will think + * the child is a conflict. */ check_exclusion_constraint(trigdata->tg_relation, indexRel, indexInfo, - &(new_row->t_self), values, isnull, + &tmptid, values, isnull, estate, false, false); } |