Distributed data access methods and apparatus for process control systems

• US 20040177060A1
• Filed: 03/03/2003
• Published: 09/09/2004
• Est. Priority Date: 03/03/2003
• Status: Active Grant

• Current Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Original Assignee: Fisher-Rosemount Systems Incorporated (Emerson Electric Company)
• Inventors: Nixon, Mark J., Gilbert, Stephen, Lucas, Mike, Chatkoff, Teresa
• Granted Patent: US 7,809,679 B2
• Time in Patent Office: Days
• US Class Current: 707/3
• CPC Class Codes: G06F 16/24561 Intermediate data storage techniques for performance improvement

Abstract

Systems and methods of accessing a database associated with a process control system send a request for information from a client application to an intermediate data server process and determine if the information is stored within a data source associated with the intermediate data server process. The systems and methods also send a request for the information from the intermediate data server process to another process if the information is not stored within the data source and access the database to retrieve the information subsequent to the other process receiving the request for the information.

Claims

1. A method of accessing a database associated with a process control system, comprising:

receiving a request for information from a client application in an intermediate data server process;

determining if the information is stored within a data source associated with the intermediate data server process;

sending a request for the information from the intermediate data server process to another process if the information is not stored within the data source; and

accessing the database to retrieve the information subsequent to the other process receiving the request for the information.

2. A method as defined in claim 1, wherein receiving the request for the information from the client application in the intermediate data server process includes receiving a request for data and at least one rule associated with the data.

3. A method as defined in claim 1, wherein receiving the request for the information from the client application in the intermediate data server process includes receiving a request for at least one of object information and rules.

4. A method as defined in claim 1, wherein determining if the information is stored within the data source includes traversing a hierarchically related first set of objects that corresponds to a subset of a second set of objects stored in the database.

5. A method as defined in claim 4, wherein traversing the hierarchically related first set of objects includes traversing a client root that corresponds to a state of the client application.

6. A method as defined in claim 1, wherein sending the request for the information from the intermediate data server process to the other process includes sending the request for the information via a database connection and a communication link.

7. A method as defined in claim 1, wherein the other process is another intermediate data server process.

8. A method as defined in claim 1, wherein accessing the database to retrieve the information subsequent to the other process receiving the request for the information includes sending a request for the information to a database accessor that is communicatively coupled to the database.

9. A method as defined in claim 1, including processing the request for the information via a session that is communicatively coupled to the data source and the database connection.

10. A method as defined in claim 1, including accessing the database to retrieve additional information, wherein the additional information is associated with a data access pattern characteristic of the client application.

11. A method as defined in claim 1, wherein sending the request for the information from the intermediate data server process to the other process includes using at least one of an extensible markup language, a transport protocol and message encoding to send the request for the information.

14. A system as defined in claim 11, wherein the request for the information includes a request for data and at least one rule associated with the data.

12. A system for accessing a database associated with a process control system, comprising:

an intermediate data server communicatively coupled to the database and programmed to;

receive a request for information from a client application;

determine if the information is stored in a data source associated with the intermediate data server; and

send a request for the information from the intermediate data server to another intermediate data server if the information is not stored in the data source.

13. A system as defined in claim 12, wherein the intermediate data server is programmed to establish a session that coordinates communications with the data source and a database connection.

15. A system as defined in claim 12, wherein the request for the information includes a request for at least one of object information and rules.

16. A system as defined in claim 12, wherein the data source includes a hierarchically related first set of objects that corresponds to a subset of a second set of objects stored in the database.

17. A system as defined in claim 12, wherein the intermediate data server is programmed to send the request for the information to the other intermediate data server via a database connection and a communication link.

18. A system as defined in claim 12, wherein the other intermediate data server accesses the database via a database accessor to retrieve the information.

19. A system as defined in claim 12, wherein the intermediate data server is programmed to send the request for the information to the other intermediate data server by using at least one of an extensible markup language, a transport protocol and message encoding.

21. A machine readable medium as defined in claim 18 having instructions stored thereon that, when executed, cause the machine to receive the request for the information from the client application in the intermediate data server process by receiving a request for data and at least one rule associated with the data.

20. A machine readable medium having instructions stored thereon that, when executed cause a machine to:

receive a request for information associated with a process control system from a client application in an intermediate data server process;

determine if the information is stored in a data source associated with the intermediate data server process;

send a request for the information from the intermediate data server process to another process if the information is not stored in the data source; and

access the database to retrieve the information subsequent to the other process receiving the request for the information.

22. A machine readable medium as defined in claim 20 having instructions stored thereon that, when executed, cause the machine to receive the request for the information from the client application in the intermediate data server process by receiving a request for at least one of object information and rules in an intermediate data server object.

23. A machine readable medium as defined in claim 20 having instructions stored thereon that, when executed, cause the machine to determine if the information is stored within the data source by traversing a hierarchically related first set of objects that corresponds to a subset of a second set of objects stored in the database.

24. A machine readable medium as defined in claim 23 having instructions stored thereon that, when executed, cause the machine to traverse the hierarchically related first set of objects by traversing a client root object that corresponds to a state of the client application.

25. A machine readable medium as defined in claim 20 having instructions stored thereon that, when executed, cause the machine to send the request for the information from the intermediate data server process to the other process by sending the request for the information via a database connection and a communication link.

26. A machine readable medium as defined in claim 20 having instructions stored thereon that, when executed, cause the machine to process the request for the information via a session that is communicatively coupled to the data source and a database connection.

27. A machine readable medium as defined in claim 20 having data stored thereon that, when executed, cause the machine to access the database to retrieve additional information, wherein the additional information is associated with a data access pattern characteristic of the client application.

28. A process control system, comprising:

a plurality of communicatively coupled intermediate data servers;

a plurality of client applications in communication with at least one of the intermediate data servers; and

a database containing information, including at least data and rules associated with the process control system, wherein the intermediate data servers are adapted to interoperate to retrieve and store in respective local data sources a subset of the information in based on the informational needs of at least some of the client applications.

29. A process control system as defined in claim 28, wherein each of the intermediate data servers is adapted to provide an intermediate data server object, a data source object, a database connection object and a session object that coordinates the activities of the intermediate data server object, the data source object and the database connection object.

30. A process control system as defined in claim 28, wherein at least two of the intermediate data servers are coupled via a communication link associated with a network.

31. A process control system as defined in claim 30, wherein each of the objects within the hierarchy of objects includes an associated object, properties and a role.

32. A process control system as defined in claim 28, wherein the intermediate data servers are adapted to communicate using an extensible markup language.

33. A process control system as defined in claim 28, wherein the client applications include a browser application.

34. A process control system as defined in claim 28, wherein the intermediate data servers are adapted to execute at least some of the rules associated with the process control system.

35. A process control system as defined in claim 28, wherein the subset of the information retrieved by each of the intermediate data servers includes information consistent with a data access characteristic of that intermediate data server.

40. A method as defined in claim 33, wherein the set of information includes information associated with at least one of the process control system and an enterprise.

36. A method of changing information within a database associated with a process control system, comprising:

sending a set of information from a first intermediate data server to a second intermediate data server;

sending the set of information from the second intermediate data server to a database server; and

writing the set of information to the database to change the information within the database.

37. A method as defined in claim 36, wherein each of the first and second intermediate data servers include a data source, a session and a database connection.

38. A method as defined in claim 36, wherein the set of information includes an extensible markup language document.

39. A method as defined in claim 36, wherein sending the set of information from the first intermediate data server to the second intermediate data server includes sending the set of information via a communication link.

41. A method of propagating a database change within a networked system, comprising:

changing a set of information within a database to form a second set of information;

sending the second set of information to a first intermediate data server within the networked system;

sending the second set of information from the first intermediate data server to a second intermediate data server; and

storing at least a portion of the second set of information in a data source associated with a client application.

42. A method as defined in claim 41, wherein sending the second set of information from the first intermediate data server to the second intermediate data server includes sending an extensible markup language document from the first intermediate data server to the second intermediate data server.

43. A method as defined in claim 41, wherein storing at least the portion of the second set of information in the data source associated with the client application includes storing information associated with information previously requested by the data source.

44. A method of accessing a database associated with a process control system, comprising:

receiving a request for data and at least one rule associated with the data from a client application in an intermediate data server process; and

accessing the database to retrieve the data and the at least one rule associated with the data.

45. A method as defined in claim 44, further comprising enforcing the at least one rule in response to a request to change at least a portion of the data.

46. A method as defined in claim 44, wherein accessing the database includes communicating with another intermediate data server process coupled to the database.

47. A method of editing a process control system database, comprising:

requesting substantially all data associated with the process control system database;

receiving the requested substantially all data associated with the process control system database in a client application;

editing at least some of the substantially all data associated with the process control system database in the client application while the client application is off-line with respect to the process control system database; and

enforcing at least one rule associated with the process control system database and accessible by the client application while the client application is off-line with respect to the process control system database.

48. A method as defined in claim 47, further comprising reconciling the at least some of the substantially all data associated with the process control system subsequent to editing.

49. A method as defined in claim 47, wherein the substantially all data associated with the process control system includes a copy of the process control system database.