Patent ID: 7302454

Claim:
A database processing method for performing backup of data used in an information processing device having a storage means, the method comprising the steps of: storing in an update bitmap management table stored in the storage means updated bit information indicating that data has been updated, when the data has been updated; commanding the backup of data corresponding to updated bit information stored in the update bitmap management table when a number of the updated bit information stored in the update bitmap management table has reached a differential backup reference value for estimating differential backup processing time; reading out the updated bit information stored in the update bitmap management table in the storage means upon receipt of the command for the backup, and obtaining the backup of the data corresponding to the update bit information stored in the update bitmap management table; estimating processing time required for the backup processing from a size of the data corresponding to the updated bit information based on the differential backup reference value; estimating processing time required for a recovery processing from the size of data corresponding to the updated bit information and estimating a reference value for determining commanding of a full backup of data stored in the storage means when a increment of the updated bits in a perdetermined time interval is less than the reference value.