1. A file storage management system for managing pages in a file, in which pages, data items belonging to a plurality of relations are stored, said file storage management system comprising: a data file for storing data items belonging to relations page by page; a page map file storing information representing positions at which data pages and empty pages are positioned in the file, the data pages storing data items belonging to relations, the empty pages storing no data item; a metamap file for storing metamap information representing whether or not the data empty pages and the data pages exist in each page map; relation group definition file for information representing whether relations are friendly relations or exclusive relations, the friendly relations being relations relevant to each other and caused to be stored close to each other, the exclusive relations being relations not relevant to each other; page management means for managing said data file; page map management means for managing said page map file; metamap management means for managing said metamap file; relation group management means for managing said relation group definition file; and page operation means for operating said page management means, said page map management means, said metamap management means, said relation group management means so that a process for allocating data items belonging to relations to pages, and a process for searching for pages to be released from management in said system and for pages storing data items to be loaded into a main memory are carried out.