SelectWithUnionQuery (children 1)
 ExpressionList (children 1)
  SelectQuery (children 1)
   ExpressionList (children 2)
    Literal \'month\'
    Function dateDiff (children 1)
     ExpressionList (children 3)
      Literal \'month\'
      Function toDateTime64 (children 1)
       ExpressionList (children 2)
        Literal \'1969-12-25 10:00:00.000\'
        Literal UInt64_3
      Function toDateTime64 (children 1)
       ExpressionList (children 2)
        Literal \'1970-01-05 10:00:00.000\'
        Literal UInt64_3
