Patent ID: 7111019

Claim:
A data warehouse system, comprising: a plurality of client devices, each for accepting a processing request from each user thereof; a server provided with a database and used for searching said database according to access requests from said client devices; a data collector, which is separate from said server and associated with said client devices and is provided with a storage device, for collecting data requested by users of said client devices and storing the data into said storage device as a replica which is partially replicating said database; and a network for connecting said client devices to said server respectively via said data collector, wherein said data collector comprises: a replica creation control means for determining whether a new replica of said database is to be created and stored in said storage device, in response to a replica creation request from one of said client devices, by referring to a replica management table which holds at least a data range and a data updating interval of each replica stored in the storage device, a query analysis unit for analyzing a query processing request from one of said client devices to select, as an object to be searched, a replica stored in said storage device or said database, a query processing unit for searching said replica stored in said storage device according to a query analysis result from said query analysis unit, and a communication control unit for selecting a procedure for accessing said server according to said query analysis result, and wherein said server comprises: a communication control unit for receiving said query analysis result transmitted from said data collector, and a query processing unit for searching the database of said server.