diff options
Diffstat (limited to 'src/backend/executor/nodeGather.c')
| -rw-r--r-- | src/backend/executor/nodeGather.c | 22 |
1 files changed, 21 insertions, 1 deletions
diff --git a/src/backend/executor/nodeGather.c b/src/backend/executor/nodeGather.c index e8d94ee6f38..3aa819f450a 100644 --- a/src/backend/executor/nodeGather.c +++ b/src/backend/executor/nodeGather.c @@ -430,6 +430,9 @@ ExecShutdownGather(GatherState *node) void ExecReScanGather(GatherState *node) { + Gather *gather = (Gather *) node->ps.plan; + PlanState *outerPlan = outerPlanState(node); + /* * Re-initialize the parallel workers to perform rescan of relation. We * want to gracefully shutdown all the workers so that they should be able @@ -443,5 +446,22 @@ ExecReScanGather(GatherState *node) if (node->pei) ExecParallelReinitialize(node->pei); - ExecReScan(node->ps.lefttree); + /* + * Set child node's chgParam to tell it that the next scan might deliver a + * different set of rows within the leader process. (The overall rowset + * shouldn't change, but the leader process's subset might; hence nodes + * between here and the parallel table scan node mustn't optimize on the + * assumption of an unchanging rowset.) + */ + if (gather->rescan_param >= 0) + outerPlan->chgParam = bms_add_member(outerPlan->chgParam, + gather->rescan_param); + + + /* + * if chgParam of subnode is not null then plan will be re-scanned by + * first ExecProcNode. + */ + if (outerPlan->chgParam == NULL) + ExecReScan(outerPlan); } |