cord by a key, retrieving a record by a key.  Moreover, traversal access to every key are provided, although the order is arbitrary.  These access methods are similar to ones of DBM (or its followers: NDBM and GDBM) library defined in the UNIX standard.  Tokyo Cabinet is an alternative for DBM because of its higher performance.</p>

<p>As for database of B+ tree, records whose keys are duplicated can be stored.  Access methods of storing, deleting, and retrieving are provided as with the database of hash ta