Fay, Sharpe, Beall, Fagan, Minnich & McKee
Database access system and method of controlling access management to a database access system for a plurality of heterogeneous database servers using SQL
 A database access system for a distributed system, in which the database access load is distributed among a plurality of gateways, and an arbitrary character code set can be used for database access. After the lapse of a predetermined time length, processings for particular database access are terminated. An error of a DBMS or a component on the gateway is detected by a client. The gateway detects an error of the client in connection. The client notifies the character code set identification information of the character code used for outputting the request to the gateway, and the gateway converts the character code for the request and a response to the client. The gateway receives an access request, secures the connection with a database access language conversion unit, and sends the language converted to a DBMS. In the absence of a response after the lapse of a predetermined time length, the connection with the database access language conversion unit is terminated and an error is notified to the client. Also, an error monitor request is outputted at regular intervals of time, and an error is notified to the client in the case where there is no response to the error monitor request after the lapse of a predetermined time length. 
Hitachi, Ltd.
Y Y Y G G Y Y
Y10S Y10S Y10S G06F G06F Y10S Y10S
additional additional additional inventional inventional additional additional
Hiromichi Hisashi Eisaku Keiichi Yusuke Satoshi
Ito Hashimoto Nishiyama Nakane Hino Kikuchi