remove_default_flag.patch

diff --git a/src/backend/catalog/partition.c b/src/backend/catalog/partition.c
index 3232844..194258d 100644
--- a/src/backend/catalog/partition.c
+++ b/src/backend/catalog/partition.c
@@ -127,9 +127,8 @@ static void get_range_key_properties(PartitionKey key, int keynum,
 						 Expr **keyCol,
 						 Const **lower_val, Const **upper_val);
 static List *get_qual_for_list(Relation parent, PartitionBoundSpec *spec);
-static List *get_qual_for_range(Relation parent, PartitionBoundSpec *spec,
-				   bool for_default);
-static List *get_range_nulltest(PartitionKey key);
+static List *get_qual_for_range(Relation parent, PartitionBoundSpec *spec);
+static List *get_range_nulltest(PartitionKey key, bool for_default);
 static List *generate_partition_qual(Relation rel);
 
 static PartitionRangeBound *make_one_range_bound(PartitionKey key, int index,
@@ -902,7 +901,7 @@ check_default_allows_bound(Relation parent, Relation default_rel,
 
 	new_part_constraints = (new_spec->strategy == PARTITION_STRATEGY_LIST)
 		? get_qual_for_list(parent, new_spec)
-		: get_qual_for_range(parent, new_spec, false);
+		: get_qual_for_range(parent, new_spec);
 	def_part_constraints =
 		get_default_part_validation_constraint(new_part_constraints);
 
@@ -1105,7 +1104,7 @@ get_qual_from_partbound(Relation rel, Relation parent,
 
 		case PARTITION_STRATEGY_RANGE:
 			Assert(spec->strategy == PARTITION_STRATEGY_RANGE);
-			my_qual = get_qual_for_range(parent, spec, false);
+			my_qual = get_qual_for_range(parent, spec);
 			break;
 
 		default:
@@ -1740,7 +1739,7 @@ get_range_key_properties(PartitionKey key, int keynum,
   * keys to be null, so emit an IS NOT NULL expression for each key column.
   */
 static List *
-get_range_nulltest(PartitionKey key)
+get_range_nulltest(PartitionKey key, bool for_default)
 {
 	List	   *result = NIL;
 	NullTest   *nulltest;
@@ -1771,7 +1770,7 @@ get_range_nulltest(PartitionKey key)
 
 		nulltest = makeNode(NullTest);
 		nulltest->arg = keyCol;
-		nulltest->nulltesttype = IS_NOT_NULL;
+		nulltest->nulltesttype = for_default? IS_NULL: IS_NOT_NULL;
 		nulltest->argisrow = false;
 		nulltest->location = -1;
 		result = lappend(result, nulltest);
@@ -1824,8 +1823,7 @@ get_range_nulltest(PartitionKey key)
  * If we end up with an empty result list, we return NULL.
  */
 static List *
-get_qual_for_range(Relation parent, PartitionBoundSpec *spec,
-				   bool for_default)
+get_qual_for_range(Relation parent, PartitionBoundSpec *spec)
 {
 	List	   *result = NIL;
 	ListCell   *cell1,
@@ -1878,15 +1876,34 @@ get_qual_for_range(Relation parent, PartitionBoundSpec *spec,
 
 			if (!bspec->is_default)
 			{
-				List	   *part_qual = get_qual_for_range(parent, bspec, true);
+				List	   *part_qual = get_qual_for_range(parent, bspec);
+				List	   *list_tmp = list_copy(part_qual);
+				ListCell   *lc;
+				int			count = 0;
+
+				foreach (lc, list_tmp)
+				{
+					Node *n = (Node *) lfirst(lc);
+
+					if (IsA(n, NullTest))
+					{
+						list_delete(part_qual, n);
+						count++;
+					}
+				}
+
+				if (count == list_length(list_tmp))
+					part_qual = NIL;
 
 				/*
 				 * AND the constraints of the partition and add to
 				 * or_expr_args
 				 */
-				or_expr_args = lappend(or_expr_args, list_length(part_qual) > 1
-									   ? makeBoolExpr(AND_EXPR, part_qual, -1)
-									   : linitial(part_qual));
+
+				if (part_qual != NIL)
+					or_expr_args = lappend(or_expr_args, list_length(part_qual) > 1
+										   ? makeBoolExpr(AND_EXPR, part_qual, -1)
+										   : linitial(part_qual));
 			}
 			ReleaseSysCache(tuple);
 		}
@@ -1900,6 +1917,8 @@ get_qual_for_range(Relation parent, PartitionBoundSpec *spec,
 							 : linitial(or_expr_args));
 			result = list_make1(makeBoolExpr(NOT_EXPR, result, -1));
 		}
+		else if (nparts != 1)
+			result = lappend(result,makeBoolExpr(OR_EXPR, get_range_nulltest(key, true), -1));
 
 		return result;
 	}
@@ -1908,8 +1928,7 @@ get_qual_for_range(Relation parent, PartitionBoundSpec *spec,
 	upper_or_start_datum = list_head(spec->upperdatums);
 	num_or_arms = key->partnatts;
 
-	if (!for_default)
-		result = get_range_nulltest(key);
+	result = get_range_nulltest(key, false);
 
 	/*
 	 * Iterate over the key columns and check if the corresponding lower and
@@ -2132,12 +2151,6 @@ get_qual_for_range(Relation parent, PartitionBoundSpec *spec,
 						 ? makeBoolExpr(OR_EXPR, upper_or_arms, -1)
 						 : linitial(upper_or_arms));
 
-	/* As noted above, caller expects the list to be non-empty. */
-	if (result == NIL)
-		result = for_default
-			? get_range_nulltest(key)
-			: list_make1(makeBoolConst(true, false));
-
 	return result;
 }