An identifier generation unit generates first identifiers corresponding to a plurality of first fragmentary data, into which first data that is stored in a database is divided. A database stores the first data and the first identifiers. The identifier generation unit generates, when the first data is updated to second data, second identifiers corresponding to a plurality of second fragmentary data into which the second data is divided. A deployment control unit determines whether the first identifiers are identical to the second identifiers which correspond to the first identifiers. The deployment control unit writes in the database the second fragmentary data corresponding to the second identifiers and the second identifiers when it is determined that the first identifiers are not identical to the second identifiers which correspond to the first identifiers.