diff options
Diffstat (limited to 'src/backend/executor/nodeHashjoin.c')
| -rw-r--r-- | src/backend/executor/nodeHashjoin.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/src/backend/executor/nodeHashjoin.c b/src/backend/executor/nodeHashjoin.c index 67c717910f5..c901a809236 100644 --- a/src/backend/executor/nodeHashjoin.c +++ b/src/backend/executor/nodeHashjoin.c @@ -454,7 +454,26 @@ ExecHashJoinImpl(PlanState *pstate, bool parallel) if (joinqual == NULL || ExecQual(joinqual, econtext)) { node->hj_MatchedOuter = true; - HeapTupleHeaderSetMatch(HJTUPLE_MINTUPLE(node->hj_CurTuple)); + + if (parallel) + { + /* + * Full/right outer joins are currently not supported + * for parallel joins, so we don't need to set the + * match bit. Experiments show that it's worth + * avoiding the shared memory traffic on large + * systems. + */ + Assert(!HJ_FILL_INNER(node)); + } + else + { + /* + * This is really only needed if HJ_FILL_INNER(node), + * but we'll avoid the branch and just set it always. + */ + HeapTupleHeaderSetMatch(HJTUPLE_MINTUPLE(node->hj_CurTuple)); + } /* In an antijoin, we never return a matched tuple */ if (node->js.jointype == JOIN_ANTI) |