Make tests fail with a useful error message

src/backend/distributed/planner/query_pushdown_planning.c

@@ -281,21 +281,23 @@ JoinTreeContainsSubqueryWalker(Node *joinTreeNode, void *context)
 bool
 WhereOrHavingClauseContainsSubquery(Query *query)
 {
-	FromExpr *joinTree = query->jointree;
-
 	if (FindNodeCheck(query->havingQual, IsNodeSubquery))
 	{
 		return true;
 	}
 
-	if (!joinTree)
+	if (!query->jointree)
 	{
 		return false;
 	}
 
-	Node *queryQuals = joinTree->quals;
-
-	return FindNodeCheck(queryQuals, IsNodeSubquery);
+	/*
+	 * We search the whole jointree here, not just the quals. The reason for
+	 * this is that the fromlist can contain other FromExpr nodes again or
+	 * JoinExpr nodes that also have quals. If that's the case we need to check
+	 * those as well if they contain andy subqueries.
+	 */
+	return FindNodeCheck((Node *) query->jointree, IsNodeSubquery);
 }
 
 

src/test/regress/expected/ch_bench_subquery_repartition.out

@@ -140,8 +140,10 @@ select s_i_id
     where
         s_i_id in (select i_id from item)
         AND s_i_id not in (select i_im_id from item);
-ERROR:  syntax error at or near "SubPlan"
-CONTEXT:  while executing command on localhost:xxxxx
+ s_i_id
+---------------------------------------------------------------------
+(0 rows)
+
 -- Subquery + repartion is not supported when it contains both an IN and a NOT IN
 -- where both subqueries return unique results
 select  s_i_id
@@ -150,8 +152,7 @@ select  s_i_id
         s_i_id in (select i_id from item)
         AND s_i_id not in (select i_id from item)
         AND s_i_id = ol_i_id;
-ERROR:  syntax error at or near "SubPlan"
-CONTEXT:  while executing command on localhost:xxxxx
+ERROR:  complex joins are only supported when all distributed tables are co-located and joined on their distribution columns
 -- Subquery + repartion is not supported when it contains both an IN and a NOT IN
 -- where the IN subquery returns unique results and the NOT IN returns non unique results
 select  s_i_id
@@ -160,8 +161,7 @@ select  s_i_id
         s_i_id in (select i_id from item)
         AND s_i_id not in (select i_im_id from item)
         AND s_i_id = ol_i_id;
-ERROR:  syntax error at or near "SubPlan"
-CONTEXT:  while executing command on localhost:xxxxx
+ERROR:  complex joins are only supported when all distributed tables are co-located and joined on their distribution columns
 -- Subquery + repartion is not supported when it contains both an IN and a NOT IN
 -- where the IN subquery returns non unique results and the NOT IN returns unique results
 select  s_i_id