SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 1)
    Function age (children 1)
     ExpressionList (children 3)
      Literal \'day\'
      Function materialize (children 1)
       ExpressionList (children 1)
        Function toDate (children 1)
         ExpressionList (children 2)
          Literal \'2015-08-18\'
          Literal \'UTC\'
      Function materialize (children 1)
       ExpressionList (children 1)
        Function toDateTime64 (children 1)
         ExpressionList (children 3)
          Literal \'2015-08-19 00:00:00\'
          Literal UInt64_3
          Literal \'UTC\'
