WIP fix router_run_modify_table(), more tests

Author: funbringer

expected/pathman_update_node.out

@@ -374,6 +374,32 @@ SELECT create_hash_partitions('test_update_node.test_hash', 'val', 3);
                       3
 (1 row)
 
+/* Shuffle rows a few times */
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+/* Check values #0 */
+SELECT tableoid::regclass, * FROM test_update_node.test_hash ORDER BY val;
+           tableoid           | val | comment 
+------------------------------+-----+---------
+ test_update_node.test_hash_2 |  10 | 1
+ test_update_node.test_hash_1 |  11 | 2
+ test_update_node.test_hash_1 |  12 | 3
+ test_update_node.test_hash_2 |  13 | 4
+ test_update_node.test_hash_1 |  14 | 5
+ test_update_node.test_hash_1 |  15 | 6
+ test_update_node.test_hash_2 |  16 | 7
+ test_update_node.test_hash_0 |  17 | 8
+ test_update_node.test_hash_1 |  18 | 9
+ test_update_node.test_hash_0 |  19 | 10
+(10 rows)
+
 /* Move all rows into single partition */
 UPDATE test_update_node.test_hash SET val = 1;
 /* Check values #1 */

sql/pathman_update_node.sql

@@ -174,6 +174,21 @@ INSERT INTO test_update_node.test_hash SELECT i, i FROM generate_series(1, 10) i
 SELECT create_hash_partitions('test_update_node.test_hash', 'val', 3);
 
 
+/* Shuffle rows a few times */
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+UPDATE test_update_node.test_hash SET val = val + 1;
+
+/* Check values #0 */
+SELECT tableoid::regclass, * FROM test_update_node.test_hash ORDER BY val;
+
+
 /* Move all rows into single partition */
 UPDATE test_update_node.test_hash SET val = 1;
 

src/partition_router.c

@@ -281,16 +281,20 @@ router_run_modify_table(PlanState *state)
 
 	mt_state = (ModifyTableState *) state;
 
+	/* Get initial signal */
 	mt_plans_old = MTHackField(mt_state, mt_nplans);
 
+restart:
 	/* Fetch next tuple */
 	slot = mt_method(state);
 
+	/* Get current signal */
 	mt_plans_new = MTHackField(mt_state, mt_nplans);
 
-	/* PartitionRouter asked us to restart */
+	/* Did PartitionRouter ask us to restart? */
 	if (mt_plans_new != mt_plans_old)
 	{
+		/* Signal points to current plan */
 		int state_idx = -mt_plans_new;
 
 		/* HACK: partially restore ModifyTable's state */
@@ -299,7 +303,7 @@ router_run_modify_table(PlanState *state)
 		MTHackField(mt_state, mt_whichplan) = state_idx;
 
 		/* Restart ModifyTable */
-		return mt_method(state);
+		goto restart;
 	}
 
 	return slot;