SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function dateDiff (children 1)
     ExpressionList (children 4)
      Literal \'day\'
      Function materialize (children 1)
       ExpressionList (children 1)
        Function toDateTime (children 1)
         ExpressionList (children 2)
          Literal \'2015-08-18 00:00:00\'
          Literal \'UTC\'
      Function toDate32 (children 1)
       ExpressionList (children 2)
        Literal \'2015-08-19\'
        Literal \'UTC\'
      Literal \'UTC\'