To minimize resources used on a client side by reducing the amount of data transferred between the client and a server when data are updated.

When the client 1 makes a request to take data out, the server 2 takes a predetermined unit amount of records out of records to be updated and transfers them to the client 1. The records are stored in a storage means 1c and displayed by a display means 1a. When data are updated on the screen, the update result is stored in a storage means 1c. Then the client 1 sends out the data stored in the storage means 1c and a next data taking-out request to the server 2. The server 2 stores the transferred updated data in an updated data storage means 2d and transfers the predetermined amount of records to the client 1. When the updating process is all completed, the data base 2a is updated with the updated data stored in the storage means 2d.