diff options
Diffstat (limited to 'src/backend/commands/explain.c')
| -rw-r--r-- | src/backend/commands/explain.c | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c index 9873022bf82..dbd27e53bc3 100644 --- a/src/backend/commands/explain.c +++ b/src/backend/commands/explain.c @@ -565,8 +565,9 @@ ExplainOnePlan(PlannedStmt *plannedstmt, IntoClause *into, ExplainState *es, * convert a QueryDesc's plan tree to text and append it to es->str * * The caller should have set up the options fields of *es, as well as - * initializing the output buffer es->str. Other fields in *es are - * initialized here. + * initializing the output buffer es->str. Also, output formatting state + * such as the indent level is assumed valid. Plan-tree-specific fields + * in *es are initialized here. * * NB: will not work on utility statements */ @@ -576,6 +577,7 @@ ExplainPrintPlan(ExplainState *es, QueryDesc *queryDesc) Bitmapset *rels_used = NULL; PlanState *ps; + /* Set up ExplainState fields associated with this plan tree */ Assert(queryDesc->plannedstmt != NULL); es->pstmt = queryDesc->plannedstmt; es->rtable = queryDesc->plannedstmt->rtable; @@ -583,6 +585,7 @@ ExplainPrintPlan(ExplainState *es, QueryDesc *queryDesc) es->rtable_names = select_rtable_names_for_explain(es->rtable, rels_used); es->deparse_cxt = deparse_context_for_plan_rtable(es->rtable, es->rtable_names); + es->printed_subplans = NULL; /* * Sometimes we mark a Gather node as "invisible", which means that it's @@ -2798,6 +2801,21 @@ ExplainSubPlans(List *plans, List *ancestors, SubPlanState *sps = (SubPlanState *) lfirst(lst); SubPlan *sp = (SubPlan *) sps->xprstate.expr; + /* + * There can be multiple SubPlan nodes referencing the same physical + * subplan (same plan_id, which is its index in PlannedStmt.subplans). + * We should print a subplan only once, so track which ones we already + * printed. This state must be global across the plan tree, since the + * duplicate nodes could be in different plan nodes, eg both a bitmap + * indexscan's indexqual and its parent heapscan's recheck qual. (We + * do not worry too much about which plan node we show the subplan as + * attached to in such cases.) + */ + if (bms_is_member(sp->plan_id, es->printed_subplans)) + continue; + es->printed_subplans = bms_add_member(es->printed_subplans, + sp->plan_id); + ExplainNode(sps->planstate, ancestors, relationship, sp->plan_name, es); } |