diff --git a/dbms/src/Interpreters/InterpreterSelectQuery.cpp b/dbms/src/Interpreters/InterpreterSelectQuery.cpp
index 11a605bf85c..59247e0f5fd 100644
--- a/dbms/src/Interpreters/InterpreterSelectQuery.cpp
+++ b/dbms/src/Interpreters/InterpreterSelectQuery.cpp
@@ -506,14 +506,15 @@ void InterpreterSelectQuery::executeAggregation(BlockInputStreams & streams, Exp
 			settings.max_threads, settings.limits.max_rows_to_group_by, settings.limits.group_by_overflow_mode), settings.asynchronous);
 		streams.resize(1);
 
-	/*	stream = maybeAsynchronous(
-			(key_names.empty()
-				? new ParallelAggregatingBlockInputStream(streams, key_names, aggregates, query.group_by_with_totals, separate_totals,
-					settings.max_threads, settings.limits.max_rows_to_group_by, settings.limits.group_by_overflow_mode)
-				: new SplittingAggregatingBlockInputStream(
-					new UnionBlockInputStream(streams, settings.max_threads), key_names, aggregates, settings.max_threads)),
-			settings.asynchronous);
-		
+	/*	if (key_names.empty())
+			stream = maybeAsynchronous(
+				new ParallelAggregatingBlockInputStream(streams, key_names, aggregates, query.group_by_with_totals, separate_totals,
+					settings.max_threads, settings.limits.max_rows_to_group_by, settings.limits.group_by_overflow_mode), settings.asynchronous);
+		else
+			stream = maybeAsynchronous(
+				new SplittingAggregatingBlockInputStream(
+					new UnionBlockInputStream(streams, settings.max_threads), key_names, aggregates, settings.max_threads), settings.asynchronous);
+
 		streams.resize(1);*/
 	}
 	else