In a DBMS, in response to a request from application programs, a base table update function updates a base table and a recovery start point, and a log recording function records update logs for the base table. Then, at predetermined timing, a backup function outputs the content of the base table to a backup file and copies the recovery start point associated with the base table to a recovery start point. Subsequently, when a user has specified a quiesce point and the base table, a copy generation function generates a target table that is a copy of the base table at the quiesce point by updating the backup file of the specified base table with ones of the update logs from the recovery start point to the quiesce point.