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 materialize (children 1)
       ExpressionList (children 1)
        Function toDate32 (children 1)
         ExpressionList (children 2)
          Literal \'2015-08-19\'
          Literal \'UTC\'
      Literal \'UTC\'