text: CREATE TEMPORARY VIEW t1 AS SELECT * FROM VALUES (1) AS GROUPING(a);
  CREATE TEMPORARY VIEW t2 AS SELECT * FROM VALUES (1) AS GROUPING(a);
  CREATE TEMPORARY VIEW t3 AS SELECT * FROM VALUES (1), (1) AS GROUPING(a);
  CREATE TEMPORARY VIEW t4 AS SELECT * FROM VALUES (1), (1) AS GROUPING(a);
  
  CREATE TEMPORARY VIEW ta AS
  SELECT a, 'a' AS tag FROM t1
  UNION ALL
  SELECT a, 'b' AS tag FROM t2;
  
  CREATE TEMPORARY VIEW tb AS
  SELECT a, 'a' AS tag FROM t3
  UNION ALL
  SELECT a, 'b' AS tag FROM t4;
  
  -- SPARK-19766 Constant alias columns in INNER JOIN should not be folded by FoldablePropagation rule
  SELECT tb.* FROM ta INNER JOIN tb ON ta.a = tb.a AND ta.tag = tb.tag;
  