From 4f7989ad8e3a58ead53106b13f818847a8fea630 Mon Sep 17 00:00:00 2001
From: Marco Slot <marco.slot@gmail.com>
Date: Fri, 12 Jun 2020 17:11:55 +0200
Subject: [PATCH] Rename WorkersContainingAllShards to
 PlacementsForWorkersContainingAllShards

---
 .../planner/multi_physical_planner.c          |  2 +-
 .../planner/multi_router_planner.c            | 22 ++++++++-----------
 .../distributed/multi_router_planner.h        |  2 +-
 3 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/src/backend/distributed/planner/multi_physical_planner.c b/src/backend/distributed/planner/multi_physical_planner.c
index 1e98892e0..e9582bab8 100644
--- a/src/backend/distributed/planner/multi_physical_planner.c
+++ b/src/backend/distributed/planner/multi_physical_planner.c
@@ -2646,7 +2646,7 @@ QueryPushdownTaskCreate(Query *originalQuery, int shardIndex,
 
 	Assert(anchorShardId != INVALID_SHARD_ID);
 
-	List *selectPlacementList = WorkersContainingAllShards(taskShardList);
+	List *selectPlacementList = PlacementsForWorkersContainingAllShards(taskShardList);
 	if (list_length(selectPlacementList) == 0)
 	{
 		ereport(ERROR, (errmsg("cannot find a worker that has active placements for all "
diff --git a/src/backend/distributed/planner/multi_router_planner.c b/src/backend/distributed/planner/multi_router_planner.c
index 0b1e35be4..a08d4c5f0 100644
--- a/src/backend/distributed/planner/multi_router_planner.c
+++ b/src/backend/distributed/planner/multi_router_planner.c
@@ -2197,7 +2197,8 @@ CreateTaskPlacementListForShardIntervals(List *shardIntervalListList, bool shard
 		/*
 		 * Determine the workers that have all shard placements, if any.
 		 */
-		List *workerList = WorkersContainingAllShards(shardIntervalListList);
+		List *shardPlacementList =
+			PlacementsForWorkersContainingAllShards(shardIntervalListList);
 
 		if (hasLocalRelation)
 		{
@@ -2207,9 +2208,8 @@ CreateTaskPlacementListForShardIntervals(List *shardIntervalListList, bool shard
 			 * If there is a local table, we only allow the local placement to
 			 * be used. If there is none, we disallow the query.
 			 */
-			foreach_ptr(taskPlacement, workerList)
+			foreach_ptr(taskPlacement, shardPlacementList)
 			{
-				/* include only the local placement */
 				if (taskPlacement->groupId == GetLocalGroupId())
 				{
 					placementList = lappend(placementList, taskPlacement);
@@ -2218,7 +2218,7 @@ CreateTaskPlacementListForShardIntervals(List *shardIntervalListList, bool shard
 		}
 		else
 		{
-			placementList = workerList;
+			placementList = shardPlacementList;
 		}
 	}
 	else if (generateDummyPlacement)
@@ -2586,22 +2586,18 @@ RelationPrunesToMultipleShards(List *relationShardList)
 
 
 /*
- * WorkersContainingSelectShards returns list of shard placements that contain all
- * shard intervals provided to the select query. It returns NIL if no placement
- * exists. The caller should check if there are any shard intervals exist for
- * placement check prior to calling this function.
+ * PlacementsForWorkersContainingAllShards returns list of shard placements for workers
+ * that contain all shard intervals in the given list of shard interval lists.
  */
 List *
-WorkersContainingAllShards(List *prunedShardIntervalsList)
+PlacementsForWorkersContainingAllShards(List *shardIntervalListList)
 {
-	ListCell *prunedShardIntervalCell = NULL;
 	bool firstShard = true;
 	List *currentPlacementList = NIL;
+	List *shardIntervalList = NIL;
 
-	foreach(prunedShardIntervalCell, prunedShardIntervalsList)
+	foreach_ptr(shardIntervalList, shardIntervalListList)
 	{
-		List *shardIntervalList = (List *) lfirst(prunedShardIntervalCell);
-
 		if (shardIntervalList == NIL)
 		{
 			continue;
diff --git a/src/include/distributed/multi_router_planner.h b/src/include/distributed/multi_router_planner.h
index 50fdd7d90..62f033fe4 100644
--- a/src/include/distributed/multi_router_planner.h
+++ b/src/include/distributed/multi_router_planner.h
@@ -56,7 +56,7 @@ extern List * TargetShardIntervalsForRestrictInfo(RelationRestrictionContext *
 												  restrictionContext,
 												  bool *multiShardQuery,
 												  Const **partitionValueConst);
-extern List * WorkersContainingAllShards(List *prunedShardIntervalsList);
+extern List * PlacementsForWorkersContainingAllShards(List *shardIntervalListList);
 extern List * IntersectPlacementList(List *lhsPlacementList, List *rhsPlacementList);
 extern DeferredErrorMessage * ModifyQuerySupported(Query *queryTree, Query *originalQuery,
 												   bool multiShardQuery,