PURPOSE: To efficiently execute a buffer search processing for deciding a hit of a buffer by controlling the buffer by classifying it into data page application and index page application.

CONSTITUTION: This system is provided with the record retrieving means 230 of a data processor 200 for receiving a record retrieval requesting signal 121 originated from the record retrieval instruction 120 of a user program 100. First of all, a buffer allocated for the highest level index page of a buffer area 300 is referred to, the page number of an index page of the next hierarchical level is obtained by a retrieval key, thereafter, the control is delivered to a buffer hit deciding means 240. The buffer bit deciding means 240 executes the hit decision of the buffer, reads-in a necessary page by a file input requesting signal 242, when it does not hit, and executes a retrieval processing.