| 摘要 |
A mechanism is described for the reliable notification to client applications of the implementation of predefined high-level document commands in a database. The database management system is issued a number of high-level document commands such as "move electronic mail message" or "add folder" which are to be implemented in the underlying database. As each high-level document command is implemented, an entry representing the high-level document command is set in a notification table stored in a persistent memory such as the database. The appropriate notification is then dispatched to any subscribing client applications. The client application then acknowledges to the database application that the notification has been received. In response, the entry is deleted in the notification table in the database. If the database management system were to fail, the system would check the notification table to see what notification it should send upon restarting.
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