1. A data sort method of rearranging records according to a specified sort key item in an ascending/descending order, comprising: an automaton generating step of generating an automaton for receiving a character string of a sort key item of each record, and for associating a record identifier with a final transition state; and an order value tuple generating step of generating an order value tuple which is a set of a record identifier of the record and an order value which is obtained by arranging the records in an ascending/descending order by scanning the automaton.