Patent ID: 6477548
Filing Date: 2002-11-05
Classification: G06F,Y10S

Abstract:
A server computer comprising:a database; transmission means for transmitting data stored in said database to a plurality of client computers which are connected via a network to said server computer, the transmission of data occurring in response to access requests of using the data, which are issued from said plurality of client computers; history storage means for storing access histories of respective client computers which have accessed said database so as to use the data stored in said database; transmission means for transmitting the data stored in said database to one client computer of the plurality of client computers which requests to change/register a content of said data stored in the database; update means for updating a content of relevant data stored in the database by the changed content of said data by receiving said changed content data transmitted from said one client computer; extraction means operated in such a manner that when the data content of said database is updated by receiving the changed data content from said one client computer, other client computers among said plurality of client computers which have accessed the database before being updated are extracted based upon said access histories stored in the history storage means; and notification information transmitting means for transmitting to said extracted client computers information that the content of said database is updated, wherein: said history storing means stores an access history of a client computer for every record contained in said database, which has accessed each of the records contained in said database; and said extracting means extracts a client computer based upon said access history of said record stored in said history storing means, said client computer having accessed a record before being updated when the record contained in the database is updated; said access issued from the client computer is a download access used to download an arbitrary record contained in said database to a client computer as the access source; and said history storing means stores an access history of said client computer which has downloaded said arbitrary record with respect to each of the records; said database stores a plurality of records; said download-history storage means stores into respective records, the download histories of the client computers functioning as access sources which have downloaded each of the respective records contained in the database; said extraction means is operated such that when the respective records contained in the database are updated, client computers which have downloaded records before said records were updated are extracted based upon said download history of said record, which is stored in said download-history storage means; and said message notification/transmission means provides notification that said record stored in the database is updated.