To update data bases distributed to each site asynchronously and to improve update processing performance in a distributed data base function.

When a data base update application 1 executes update processing on an original data base, the update of the original data base 2 is detected by a replica update log detecting means 4 when an update log at that time is logged, and the data base 8A that is a corresponding replica is recognized by a replica update transaction transfer means 5, and the transfer of the replica updata transaction to the site B is executed. The transaction is received by a replica update transaction receiving means 6, and the update of the data base 8A is executed, and the asynchronous update of the data base is completed. Also, the execution of the replica update transaction is performed asynchronously with that of the data base update application 1 immediately after the completion of the update of its own site.