PURPOSE: To avoid destroying a table due to a logical failure of software and to secure the safety of system operation by totally dealing with the possibility of table updating or the necessity of journal acquisition.

CONSTITUTION: An element updating function 3-4, when receiving a request for table updating, uses a specified key, if updating possibility information stored in advance in a management table 5 corresponding to a specified table name indicates that updating is possible, to access the table 5 to table elements to update the table. A Journal acquisition function 3-6, if the request is for journal acquisition, prepares and stores it in a journal file 8 prepared in advance if journal acquisition necessity information is stored in advance in the management table 5 corresponding to a specified table name. Further, an exclusive control section 3-7 inhibits the table access system from accessing another table during the execution of table accessing. With this, table destroying due to a logical failure of software is avoided and the safety of operation of the system is secured.