3 files changed, 93 insertions, 15 deletions

diff --git a/src/backend/executor/execPartition.c b/src/backend/executor/execPartition.c
index 011e3cff1ad..8061c7e449d 100644
--- a/src/backend/executor/execPartition.c
+++ b/src/backend/executor/execPartition.c
@@ -253,16 +253,25 @@ ExecFindPartition(ResultRelInfo *resultRelInfo, PartitionDispatch *pd,
 		partdesc = RelationGetPartitionDesc(rel);
 
 		/*
-		 * Convert the tuple to this parent's layout, if different from the
-		 * current relation.
+		 * Use the slot dedicated to this level's parent.  All parents except
+		 * the root have a dedicated slot.  For the root parent, we just use
+		 * the original input slot.
 		 */
-		myslot = dispatch->tupslot;
-		if (myslot != NULL && map != NULL)
+		myslot = dispatch->tupslot == NULL ? slot : dispatch->tupslot;
+
+		/*
+		 * If the tuple layout of this level's parent is different from the
+		 * previous level's parent, convert the tuple and store it into its
+		 * dedicated slot.
+		 */
+		if (myslot != slot)
 		{
-			tuple = do_convert_tuple(tuple, map);
+			if (map != NULL)
+				tuple = do_convert_tuple(tuple, map);
 			ExecStoreTuple(tuple, myslot, InvalidBuffer, true);
-			slot = myslot;
 		}
+		else
+			Assert(map == NULL);
 
 		/*
 		 * Extract partition key from tuple. Expression evaluation machinery
@@ -272,8 +281,8 @@ ExecFindPartition(ResultRelInfo *resultRelInfo, PartitionDispatch *pd,
 		 * partitioning level has different tuple descriptor from the parent.
 		 * So update ecxt_scantuple accordingly.
 		 */
-		ecxt->ecxt_scantuple = slot;
-		FormPartitionKeyDatum(dispatch, slot, estate, values, isnull);
+		ecxt->ecxt_scantuple = myslot;
+		FormPartitionKeyDatum(dispatch, myslot, estate, values, isnull);
 
 		/*
 		 * Nothing for get_partition_for_tuple() to do if there are no
@@ -309,19 +318,19 @@ ExecFindPartition(ResultRelInfo *resultRelInfo, PartitionDispatch *pd,
 			dispatch = pd[-dispatch->indexes[cur_index]];
 
 			/*
-			 * Release the dedicated slot, if it was used.  Create a copy of
-			 * the tuple first, for the next iteration.
+			 * Make a copy of the tuple for the next level of routing.  If
+			 * this level's parent had a dedicated slot, we must clear its
+			 * tuple too, which would be the copy we made in the last
+			 * iteration.
 			 */
-			if (slot == myslot)
-			{
-				tuple = ExecCopySlotTuple(myslot);
+			tuple = ExecCopySlotTuple(myslot);
+			if (myslot != slot)
 				ExecClearTuple(myslot);
-			}
 		}
 	}
 
 	/* Release the tuple in the lowest parent's dedicated slot. */
-	if (slot == myslot)
+	if (myslot != slot)
 		ExecClearTuple(myslot);
 
 	/* A partition was not found. */
diff --git a/src/test/regress/expected/insert.out b/src/test/regress/expected/insert.out
index 5edf2693679..13f53e36490 100644
--- a/src/test/regress/expected/insert.out
+++ b/src/test/regress/expected/insert.out
@@ -629,6 +629,47 @@ select tableoid::regclass, * from mlparted_def;
  mlparted_defd | 70 | 100 | 
 (4 rows)
 
+-- Check multi-level tuple routing with attributes dropped from the
+-- top-most parent.  First remove the last attribute.
+alter table mlparted add d int, add e int;
+alter table mlparted drop e;
+create table mlparted5 partition of mlparted
+  for values from (1, 40) to (1, 50) partition by range (c);
+create table mlparted5_ab partition of mlparted5
+  for values from ('a') to ('c') partition by list (c);
+create table mlparted5_a partition of mlparted5_ab for values in ('a');
+create table mlparted5_b (d int, b int, c text, a int);
+alter table mlparted5_ab attach partition mlparted5_b for values in ('b');
+truncate mlparted;
+insert into mlparted values (1, 2, 'a', 1);
+insert into mlparted values (1, 40, 'a', 1);  -- goes to mlparted5_a
+insert into mlparted values (1, 45, 'b', 1);  -- goes to mlparted5_b
+select tableoid::regclass, * from mlparted order by a, b, c, d;
+  tableoid   | a | b  | c | d 
+-------------+---+----+---+---
+ mlparted11  | 1 |  2 | a | 1
+ mlparted5_a | 1 | 40 | a | 1
+ mlparted5_b | 1 | 45 | b | 1
+(3 rows)
+
+alter table mlparted drop d;
+truncate mlparted;
+-- Remove the before last attribute.
+alter table mlparted add e int, add d int;
+alter table mlparted drop e;
+insert into mlparted values (1, 2, 'a', 1);
+insert into mlparted values (1, 40, 'a', 1);  -- goes to mlparted5_a
+insert into mlparted values (1, 45, 'b', 1);  -- goes to mlparted5_b
+select tableoid::regclass, * from mlparted order by a, b, c, d;
+  tableoid   | a | b  | c | d 
+-------------+---+----+---+---
+ mlparted11  | 1 |  2 | a | 1
+ mlparted5_a | 1 | 40 | a | 1
+ mlparted5_b | 1 | 45 | b | 1
+(3 rows)
+
+alter table mlparted drop d;
+drop table mlparted5;
 -- check that message shown after failure to find a partition shows the
 -- appropriate key description (or none) in various situations
 create table key_desc (a int, b int) partition by list ((a+0));
diff --git a/src/test/regress/sql/insert.sql b/src/test/regress/sql/insert.sql
index a7f659bc2b4..4d1c92a54df 100644
--- a/src/test/regress/sql/insert.sql
+++ b/src/test/regress/sql/insert.sql
@@ -401,6 +401,34 @@ insert into mlparted values (70, 100);
 
 select tableoid::regclass, * from mlparted_def;
 
+-- Check multi-level tuple routing with attributes dropped from the
+-- top-most parent.  First remove the last attribute.
+alter table mlparted add d int, add e int;
+alter table mlparted drop e;
+create table mlparted5 partition of mlparted
+  for values from (1, 40) to (1, 50) partition by range (c);
+create table mlparted5_ab partition of mlparted5
+  for values from ('a') to ('c') partition by list (c);
+create table mlparted5_a partition of mlparted5_ab for values in ('a');
+create table mlparted5_b (d int, b int, c text, a int);
+alter table mlparted5_ab attach partition mlparted5_b for values in ('b');
+truncate mlparted;
+insert into mlparted values (1, 2, 'a', 1);
+insert into mlparted values (1, 40, 'a', 1);  -- goes to mlparted5_a
+insert into mlparted values (1, 45, 'b', 1);  -- goes to mlparted5_b
+select tableoid::regclass, * from mlparted order by a, b, c, d;
+alter table mlparted drop d;
+truncate mlparted;
+-- Remove the before last attribute.
+alter table mlparted add e int, add d int;
+alter table mlparted drop e;
+insert into mlparted values (1, 2, 'a', 1);
+insert into mlparted values (1, 40, 'a', 1);  -- goes to mlparted5_a
+insert into mlparted values (1, 45, 'b', 1);  -- goes to mlparted5_b
+select tableoid::regclass, * from mlparted order by a, b, c, d;
+alter table mlparted drop d;
+drop table mlparted5;
+
 -- check that message shown after failure to find a partition shows the
 -- appropriate key description (or none) in various situations
 create table key_desc (a int, b int) partition by list ((a+0));