Methods and systems for performing reliable asynchronous notification of high-level document operations

• US 6,868,418 B1
• Filed: 10/04/2000
• Issued: 03/15/2005
• Est. Priority Date: 10/04/2000
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Avner, Jon B., Terek, Soner F.
• Primary Examiner(s): Metjahic, Safet
• Assistant Examiner(s): Santos, Patrick J. D.
• Application Number:
  US09/680,045
• Time in Patent Office: 1,623 Days
• Field of Search: 707/100, 707/104.1, 707/104
• US Class Current: 1/1
• CPC Class Codes: G06F 16/2372 Updates performed during offline database operations
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing
• CPC Class Codes: Y10S 707/99948 Application of database or data structure, e.g. distributed, multimedia, or image

Abstract

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. This entry may be set in the same atomic transaction as the other table updates needed to implement the high-level document command. 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.

Claims

1. In a computing system comprised of an operating system and client applications, and that includes,

external to the operating system, i) a database application for generating high-level document commands that relate to operations to be performed on a document such as a folder, a file, a message or other such entities that are identified at the level of client applications that use the system, and ii) a database engine for receiving the high-level commands from the database application and then implementing them by executing object commands passed to an operating system, and

internal to the operating system, a separate notification database containing one or more tables each comprised of objects that define various properties of one or more documents, and wherein the objects contained in the database tables are updated in response to the object commands received from the operating system,

a method for asynchronously notifying client applications of the, implementation of particular high-level document commands so that such notification survives even failures of either the database engine or client applications, and wherein the method is comprised of performing the following acts:

the database application issuing one or more high-level document commands which are to be implemented;

either i) before implementing an issued high-level document command, or ii) at the same time that any other table of the database is updated, the database engine altering a persistently stored notification table by creating a notification entry to reflect the implementation of the issued high-level document command, with the result that the client applications do not affect the implementation of the high-level document command since the implementation takes place prior to notification of the client applications, even in the event of failure of either database or the client application, because either,

for case i), no tables in the database are updated until such failure is restored and notification of implementation is verified by at least one of the client applications to the database engine of the operating system, or

for case ii), all tables in the database are updated in the same transaction used to create the notification entry when updating the persistently stored notification table of the database engine of the operating system; and

dispatching from the operating system a notification of the implementation of the issued high-level document command to one or more client applications requiring such notification;

receiving acknowledgement from at least one of the one or more client applications that the notification has been received; and

in response to receiving acknowledgement, the database engine altering the notification table to reflect that no client applications any longer treed to be notified of the implementation of the high-level document command.

2. The method in accordance with claim 1, wherein the notification table is stored in the database.

3. The method in accordance with claim 1, wherein the act of dispatching a notification of the implementation to the one or more client applications requiring such notification comprises an act of transmitting a message to a machine that hosts the client application, the machine that host the client application being different than the machine that hosts the database management system.

4. The method in accordance with claim 1, wherein the act of dispatching a notification of the implementation to the one or more client applications requiring such notification comprises an act of passing the notification through a function call to the identified client application, the client application hosted by the same machine as at least the portion of the database management system responsible for performing the act of dispatching the notification.

5. The method in accordance with claim 1, wherein the act of implementing a high-level document command in the database and the act of altering a persistently stored notification table to reflect the implementation occur in the same transaction of a database engine.

6. The method in accordance with claim 1, wherein the act of implementing the high-level document command in the database comprises an act of moving the document.

7. The method in accordance with claim 1, wherein the act of implementing the high-level document command in the database comprises an act of deleting the document.

8. The method in accordance with claim 1, wherein the act of implementing the high-level document command in the database comprises an act of copying the document.

9. The method in accordance with claim 1, wherein the act of implementing the high-level document command in the database comprises an act of adding the document.

10. The method in accordance with claim 1, wherein the act of implementing the high-level document command in the database comprises an act of updating the document.

11. The method in accordance with claim 1, wherein the received acknowledgement indicates that the client application has implemented processes in response to the notification.

12. In a computing system comprised of an operating system and client applications, and that includes,

external to the operating system, i) a database application for generating high-level document commands that relate to operations to be performed on a document such as a folder, a file, a message or other such entities that are identified at the level of client applications that use the system, and ii) a database engine for receiving the high-level commands from the database application and then implementing them by executing object commands passed to an operating system, and

internal to the operating system, a separate notification database containing one or more tables each comprised of objects that define various properties of one or more documents, and wherein the objects contained in the database tables are updated in response to the object commands received from the operating system,

a computer program product comprised of computer-executable instructions for implementing a method for asynchronously notifying client applications of the implementation of particular high-level document commands so that such notification survives even failures of either the database engine or client applications, and wherein the method is comprised of performing the following acts:

the database application issuing one or more high-level document commands which are to be implemented;

either i) before implementing an issued high-level document command, or ii) at the same time that any other table of the database is updated, the database engine altering a persistently stored notification table by creating a notification entry to reflect the implementation of the issued high-level document command, with the result that the client applications do not affect the implementation of the high-level document command since the implementation takes place prior to notification of the client applications, even in the event of failure of either database or the client application, because either,

for case i), no tables in the database are updated until such failure is restored and notification of implementation is verified by at least one of the client applications to the database engine of the operating system, or

for case ii), all tables in the database are updated in the same transaction used to created the notification entry when updating the persistently stored notification table of the database engine of the operating system; and

dispatching from the operating system a notification of the implementation of the issued high-level document command to one or more client applications requiring such notification;

receiving acknowledgement from at least one of the one or more client applications that the notification has been received; and

in response to receiving acknowledgement, the database engine altering the notification table to reflect that no client applications any longer need to be notified of the implementation of the high-level document command.

13. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing a notification of the implementation to be dispatched to the one or more identified client applications comprise computer-executable instructions for performing an act of causing a message to be transmitted to a machine that hosts the client application, the machine that hosts the client application being different than the machine that hosts the database management system.

14. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing a notification of the implementation to be dispatched to the one or more identified client applications comprises computer-executable instructions for performing an act of causing the notification to be passed through a function call to the identified client application, the client application hosted by the same machine;

as at least the portion of the database management system responsible for performing the act of dispatching the notification.

15. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing the high-level document command to be implemented in the database comprise computer-executable instructions for performing an act of moving the document.

16. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing the high-level document command to be implemented in the database comprise computer-executable instructions for performing an act of deleting the document.

17. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing the high-level document command to be implemented in the database comprise computer-executable instructions for performing an act of copying the document.

18. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing the high-level document command to be implemented in the database comprises comprise computer-executable instructions for performing an act of adding the document.

19. The computer program product in accordance with claim 12, wherein the computer-executable instructions for performing the act of causing the high-level document command to be implemented in the database comprise computer-executable instructions for performing an act of updating the document.