Merge pull request #1146 from citusdata/explain_duplication

Don't duplicate planner logic in multi_explain.c

src/backend/distributed/planner/multi_explain.c

@@ -52,8 +52,6 @@
 
 
 /* Config variables that enable printing distributed query plans */
-bool ExplainMultiLogicalPlan = false;
-bool ExplainMultiPhysicalPlan = false;
 bool ExplainDistributedQueries = true;
 bool ExplainAllTasks = false;
 
@@ -79,6 +77,9 @@ static void ExplainTask(Task *task, int placementIndex, List *explainOutputList,
 static void ExplainTaskPlacement(ShardPlacement *taskPlacement, List *explainOutputList,
 								 ExplainState *es);
 static StringInfo BuildRemoteExplainQuery(char *queryString, ExplainState *es);
+static void MultiExplainOnePlan(PlannedStmt *plan, IntoClause *into,
+								ExplainState *es, const char *queryString,
+								ParamListInfo params, const instr_time *planDuration);
 
 /* Static Explain functions copied from explain.c */
 static void ExplainOpenGroup(const char *objtype, const char *labelname,
@@ -100,17 +101,10 @@ void
 MultiExplainOneQuery(Query *query, IntoClause *into, ExplainState *es,
 					 const char *queryString, ParamListInfo params)
 {
-	MultiPlan *multiPlan = NULL;
-	CmdType commandType = CMD_UNKNOWN;
-	PlannedStmt *initialPlan = NULL;
-	Job *workerJob = NULL;
-	bool routerExecutablePlan = false;
 	instr_time planStart;
 	instr_time planDuration;
-	Query *originalQuery = NULL;
-	RelationRestrictionContext *restrictionContext = NULL;
-	bool localQuery = !NeedsDistributedPlanning(query);
 	int cursorOptions = 0;
+	PlannedStmt *plan = NULL;
 
 #if PG_VERSION_NUM >= 90600
 
@@ -124,11 +118,7 @@ MultiExplainOneQuery(Query *query, IntoClause *into, ExplainState *es,
 	}
 #endif
 
-	/* handle local queries in the same way as ExplainOneQuery */
-	if (localQuery)
-	{
-		PlannedStmt *plan = NULL;
-
+	/* plan query, just like ExplainOneQuery does */
 	INSTR_TIME_SET_CURRENT(planStart);
 
 	/* plan the query */
@@ -137,29 +127,33 @@ MultiExplainOneQuery(Query *query, IntoClause *into, ExplainState *es,
 	INSTR_TIME_SET_CURRENT(planDuration);
 	INSTR_TIME_SUBTRACT(planDuration, planStart);
 
+	/* if not a distributed query, use plain explain infrastructure */
+	if (!HasCitusToplevelNode(plan))
+	{
 		/* run it (if needed) and produce output */
 		ExplainOnePlan(plan, into, es, queryString, params, &planDuration);
-
-		return;
+	}
+	else
+	{
+		MultiExplainOnePlan(plan, into, es, queryString, params, &planDuration);
+	}
 }
 
+
 /*
-	 * standard_planner scribbles on it's input, but for deparsing we need the
-	 * unmodified form. So copy once we're sure it's a distributed query.
+ * MultiExplainOnePlan explains the plan for an individual distributed query.
  */
-	originalQuery = copyObject(query);
-
-	/* measure the full planning time to display in EXPLAIN ANALYZE */
-	INSTR_TIME_SET_CURRENT(planStart);
-
-	restrictionContext = CreateAndPushRestrictionContext();
-
-	PG_TRY();
+static void
+MultiExplainOnePlan(PlannedStmt *plan, IntoClause *into,
+					ExplainState *es, const char *queryString,
+					ParamListInfo params, const instr_time *planDuration)
 {
-		/* call standard planner to modify the query structure before multi planning */
-		initialPlan = standard_planner(query, cursorOptions, params);
+	MultiPlan *multiPlan = NULL;
+	CmdType commandType = CMD_UNKNOWN;
+	Job *workerJob = NULL;
+	bool routerExecutablePlan = false;
 
-		commandType = initialPlan->commandType;
+	commandType = plan->commandType;
 	if (commandType == CMD_INSERT || commandType == CMD_UPDATE ||
 		commandType == CMD_DELETE)
 	{
@@ -171,38 +165,7 @@ MultiExplainOneQuery(Query *query, IntoClause *into, ExplainState *es,
 		}
 	}
 
-		multiPlan = CreatePhysicalPlan(originalQuery, query, restrictionContext);
-	}
-	PG_CATCH();
-	{
-		PopRestrictionContext();
-		PG_RE_THROW();
-	}
-	PG_END_TRY();
-
-	PopRestrictionContext();
-
-	INSTR_TIME_SET_CURRENT(planDuration);
-	INSTR_TIME_SUBTRACT(planDuration, planStart);
-
-	if (ExplainMultiLogicalPlan)
-	{
-		MultiTreeRoot *multiTree = MultiLogicalPlanCreate(query);
-		char *logicalPlanString = CitusNodeToString(multiTree);
-		char *formattedPlanString = pretty_format_node_dump(logicalPlanString);
-
-		appendStringInfo(es->str, "logical plan:\n");
-		appendStringInfo(es->str, "%s\n", formattedPlanString);
-	}
-
-	if (ExplainMultiPhysicalPlan)
-	{
-		char *physicalPlanString = CitusNodeToString(multiPlan);
-		char *formattedPlanString = pretty_format_node_dump(physicalPlanString);
-
-		appendStringInfo(es->str, "physical plan:\n");
-		appendStringInfo(es->str, "%s\n", formattedPlanString);
-	}
+	multiPlan = GetMultiPlan(plan);
 
 	if (!ExplainDistributedQueries)
 	{
@@ -268,8 +231,6 @@ MultiExplainOneQuery(Query *query, IntoClause *into, ExplainState *es,
 
 	if (!routerExecutablePlan)
 	{
-		PlannedStmt *masterPlan = MultiQueryContainerNode(initialPlan, multiPlan);
-
 		if (es->format == EXPLAIN_FORMAT_TEXT)
 		{
 			appendStringInfoSpaces(es->str, es->indent * 2);
@@ -279,7 +240,7 @@ MultiExplainOneQuery(Query *query, IntoClause *into, ExplainState *es,
 
 		ExplainOpenGroup("Master Query", "Master Query", false, es);
 
-		ExplainMasterPlan(masterPlan, into, es, queryString, params, &planDuration);
+		ExplainMasterPlan(plan, into, es, queryString, params, planDuration);
 
 		ExplainCloseGroup("Master Query", "Master Query", false, es);
 

src/backend/distributed/planner/multi_planner.c

@@ -36,10 +36,15 @@ static List *relationRestrictionContextList = NIL;
 
 /* local function forward declarations */
 static void CheckNodeIsDumpable(Node *node);
-
-
-/* local function forward declarations */
 static char * GetMultiPlanString(PlannedStmt *result);
+static PlannedStmt * MultiQueryContainerNode(PlannedStmt *result,
+											 struct MultiPlan *multiPlan);
+static struct MultiPlan * CreatePhysicalPlan(Query *originalQuery, Query *query,
+											 RelationRestrictionContext *
+											 restrictionContext);
+static RelationRestrictionContext * CreateAndPushRestrictionContext(void);
+static RelationRestrictionContext * CurrentRestrictionContext(void);
+static void PopRestrictionContext(void);
 
 
 /* Distributed planner hook */
@@ -123,7 +128,7 @@ multi_planner(Query *parse, int cursorOptions, ParamListInfo boundParams)
  * target shards. SELECT queries go through the full logical plan/optimize/
  * physical plan process needed to produce distributed query plans.
  */
-MultiPlan *
+static MultiPlan *
 CreatePhysicalPlan(Query *originalQuery, Query *query,
 				   RelationRestrictionContext *restrictionContext)
 {

src/backend/distributed/shared_library_init.c

@@ -295,30 +295,6 @@ RegisterCitusConfigVariables(void)
 		0,
 		NULL, NULL, NULL);
 
-	DefineCustomBoolVariable(
-		"citus.explain_multi_logical_plan",
-		gettext_noop("Enables Explain to print out distributed logical plans."),
-		gettext_noop("We use this private configuration entry as a debugging aid. "
-					 "If enabled, the Explain command prints out the optimized "
-					 "logical plan for distributed queries."),
-		&ExplainMultiLogicalPlan,
-		false,
-		PGC_USERSET,
-		GUC_NO_SHOW_ALL,
-		NULL, NULL, NULL);
-
-	DefineCustomBoolVariable(
-		"citus.explain_multi_physical_plan",
-		gettext_noop("Enables Explain to print out distributed physical plans."),
-		gettext_noop("We use this private configuration entry as a debugging aid. "
-					 "If enabled, the Explain command prints out the physical "
-					 "plan for distributed queries."),
-		&ExplainMultiPhysicalPlan,
-		false,
-		PGC_USERSET,
-		GUC_NO_SHOW_ALL,
-		NULL, NULL, NULL);
-
 	DefineCustomBoolVariable(
 		"citus.explain_distributed_queries",
 		gettext_noop("Enables Explain for distributed queries."),

src/include/distributed/multi_explain.h

@@ -13,8 +13,6 @@
 #include "executor/executor.h"
 
 /* Config variables managed via guc.c to explain distributed query plans */
-extern bool ExplainMultiLogicalPlan;
-extern bool ExplainMultiPhysicalPlan;
 extern bool ExplainDistributedQueries;
 extern bool ExplainAllTasks;
 

src/include/distributed/multi_planner.h

@@ -53,16 +53,8 @@ extern PlannedStmt * multi_planner(Query *parse, int cursorOptions,
 
 extern bool HasCitusToplevelNode(PlannedStmt *planStatement);
 struct MultiPlan;
-extern struct MultiPlan * CreatePhysicalPlan(Query *originalQuery, Query *query,
-											 RelationRestrictionContext *
-											 restrictionContext);
 extern struct MultiPlan * GetMultiPlan(PlannedStmt *planStatement);
-extern PlannedStmt * MultiQueryContainerNode(PlannedStmt *result,
-											 struct MultiPlan *multiPlan);
 extern void multi_relation_restriction_hook(PlannerInfo *root, RelOptInfo *relOptInfo,
 											Index index, RangeTblEntry *rte);
-extern RelationRestrictionContext * CreateAndPushRestrictionContext(void);
-extern RelationRestrictionContext * CurrentRestrictionContext(void);
-extern void PopRestrictionContext(void);
 
 #endif /* MULTI_PLANNER_H */