SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function toTypeName (alias x) (children 1)
     ExpressionList (children 1)
      Function sum (children 1)
       ExpressionList (children 1)
        Function in (children 1)
         ExpressionList (children 2)
          Function toNullable (children 1)
           ExpressionList (children 1)
            Literal \'a\'
          Function toNullable (children 1)
           ExpressionList (children 1)
            Literal \'a\'
