JPH0319981B

PURPOSE:To decrease the number of times of accessing to an auxiliary memory, and to secure a high responsiveness by reducing the relation of a data access command from an application program and a physical structure of a data base. CONSTITUTION:An index record in a zone file is made to have a cache memory- like function of a circulating object data, and while a circulating object exists in some zone, a necessary data in its zone is chopped by the index record, so as to be pretended as if all necessary items exist in the zone file. That is to say, when the index record is moved to a zone 2 from a zone 1, an item A is carried over, but an item B is saved to the area concerned in an object file, and on the contrary, an item C is chopped automatically to the index reocrd from the object file. Accordingly, a data of the necessary item C can be answered by only the zone file.