A distributed database system comprising:
- a database administration apparatus, which administers a database allocated on network,
- a topology administration server for distributing database of said database administration apparatus, and
- a plurality of computers, which are allocated in an administration domain administered on network by said topology administration server;
- wherein
- said topology administration server comprises:
- storage for topology information, which stores topology information, including certain information correlating a database object identifier, which is information for identifying a database object administered by said database administration apparatus, with an identifier of a database administration apparatus for identifying a database administration apparatus administering the database object;
- a receiver for a cache request, which receives a cache request including said database object identifier transmitted from at least one or more of said computers for caching a database object identified by said database object identifiers;
- an acquisition unit for an identifier of a database administration apparatus, which acquires a corresponding identifier of a database administration apparatus from said storage for topology information based on the database object identifier included in the cache request received by said receiver for a cache request;
- a transferring unit for a cache request, which transfers said cache request to the database administration apparatus identified by the identifier of the database administration apparatus, in which said identifier is acquired by said acquisition unit for an identifier of a database administration apparatus;
- said computer comprises:
- a transmitter for a cache request, which transfers a cache request,
- a receiver for a database object, which receives the database object returned in accordance with the transmission of the cache request by said transmitter for a cache request;
- and
- a caching unit for a database object, which caches a database object received by the receiver for a database object;
- and
- said database administration apparatus comprises:
- a receiver for a cache request, which receives the cache request transferred by the topology administration server, and
- a copy and transmission unit for a database object, which copies and transmits the database object in accordance with the cache request received by the receiver for a cache request.