Method and system for propagating data changes through data objects

• US 20020165724A1
• Filed: 02/23/2001
• Published: 11/07/2002
• Est. Priority Date: 02/07/2001
• Status: Abandoned Application

• Current Assignee: Bartus C. Blankesteijn
• Original Assignee: Bartus C. Blankesteijn
• Inventors: Blankesteijn, Bartus C.
• Application Number:
  US09/791,292
• Publication Number:
  US 20020165724A1
• Time in Patent Office: Days
• US Class Current: 705/1
• CPC Class Codes: G06F 16/2308 Concurrency control transaction processing G06F9/466
• CPC Class Codes: G06F 16/2343 Locking methods, e.g. distributed locking or locking implementation details
• CPC Class Codes: G06F 16/27 Replication, distribution or synchronisation of data between databases or within a distributed database system; Distributed database system architectures therefor
• CPC Class Codes: G06Q 30/06 Buying, selling or leasing transactions

Abstract

A method and system are disclosed for propagating data changes from a data change source to a data change destination via a replication mechanism. After receiving a change to a data entry by the data change source, the replication mechanism builds a data change object specifying a first change. After performing optional formatting and filtering operations, the replication mechanism renders the data change object available for transmission to at least the data change destination. The system provides the data change object to the data change destination. In an embodiment of the invention, the data change object is combined with a prior change on the same object to render a “net” change on the data object. The disclosed invention is incorporated by way of example into a database application/system for maintaining business objects such as sales orders, shipping, and other business transactions. However, it is applicable to a variety of data change propagation circumstances including applications running on a same computer system that utilize different data sets having potentially different data formats.

Claims

1. A method for propagating, by a replication mechanism, changes to a data entry made by a data change source, the method comprising the steps of:

first receiving, by the replication mechanism, a change to a data entry by the data change source;

building, from the change to the data entry, a data change object specifying a first change on an identified data construct;

rendering the data change object available for transmission to at least a data change destination; and

providing the data change object to the data change destination.

2. The method of claim 1 further comprising the step of:

combining the change with other changes within the data change object to render a net change object representing the combined changes.

3. The method of claim 2 wherein the combining step is performed after the building step, and is performed upon the data change object.

4. The method of claim 1 wherein the building step comprises:

inserting, within the data change object, at least one action attribute specifying at least one action performed upon the identified data construct.

5. The method of claim 4 wherein the data change object is a multilevel object structure and wherein the inserting step comprises:

specifying a first action on the data change object at a first level of the data change object; and

specifying a second action on the data change object at a second level of the data change object.

6. The method of claim 5 wherein the data change object comprises a set of tuples, and wherein the first action and second action are specified with reference to individual ones of the tuples.

7. The method of claim 1 further comprising the step of:

applying a filter to the change.

8. The method of claim 1 further comprising the steps of:

retrieving supplementary data; and

incorporating the supplementary data into the data change object.

9. The method of claim 8 further comprising:

synchronizing the change to the data entry and the supplementary data.

10. The method of claim 9, wherein the change to the data entry by the data change source occurs at a first time, T1, and the retrieving supplementary data step occurs at a subsequent time T3, wherein the synchronizing step comprises:

correcting a synchronization inconsistency arising from a transaction executed at a time T2, occurring between the changes at T1 and T3, pertaining to the supplementary data.

11. The method of claim 10 wherein the correcting a synchronization inconsistency step comprises:

reversing a change to the supplementary data arising from the transaction at time T2, and wherein the reversing a change step is performed prior to the rendering step.

12. The method of claim 10 wherein the rendering step is not performed until the server mechanism processes all changes having a potential impact upon the synchronization of the change to the data entry and the supplementary data.

13. The method of claim 12 wherein the rendering step is performed after processing all transactions committed to the database between T1 and T3.

14. The method of claim 10, wherein the correcting a synchronization inconsistency step further comprises the steps of:

placing the data change object in a queue of data change objects based upon execution order of data change transactions; and

de-queuing the data change object when the data change object is at the head of the queue and the correcting a synchronization inconsistency step is complete.

15. The method of claim 9 further comprising the steps of:

applying a first filter to data changes specified in the data change object prior to the synchronizing step; and

applying a second filter to unchanged data specified in the data change object subsequent to the synchronizing step.

16. The method of claim 1 further comprising:

creating a second data change object on a second identified data construct; and

synchronizing the changed data in the data change object and the second data change object.

17. The method of claim 16 wherein the first data change object and second data change object are of different types.

18. The method of claim 1 wherein the building step is performed in response to a notification mechanism activated by the data change source submitting the change to the data entry, thereby facilitating near-real time processing of changes.

19. The method of claim 1 wherein the data change object corresponds to a business entity.

20. The method of claim 1 wherein the data change object is specified using self-identifying data type descriptors.

21. The method of claim 20 wherein the self-identifying data type descriptors comprise XML tags.

22. The method of claim 1 further comprising:

transforming the change to the database entry by the data change source from a first data type to render a data change in a second data type; and

incorporating the data change in the second data type into the data change object.

23. The method of claim 1 further comprising:

reformatting the change to the data entry by the data change source from a first format to render a data change in a second format; and

incorporating the data change in the second format into the data change object.

24. The method of claim 1 wherein the change to the data entry by the data change source is associated with at least a second change within a single data change transaction, and wherein the building step is performed upon both the change and the second change as a single atomic work unit.

25. The method of claim 1 further comprising maintaining a set of data change store state variables to facilitate coordinating storing and retrieving of data change objects from a storage location.

26. The method of claim 25 wherein the rendering step comprises placing the data change object within a data change store that includes a net data change object associated with a period of transactions, and further comprising the step of freezing the period in response to a request to retrieve the data change objects associated with the period of transactions.

27. The method of claim 1 wherein the data change source corresponds to a first application and the data change destination corresponds to a second application.

28. The method of claim 1 wherein the identified data construct is an identified data object.

29. The method of claim 1 wherein the replication mechanism is incorporated into a data replication server.

30. The method of claim 1 wherein the data entry is associated with a database.

31. A computer-readable medium storing computer executable instructions to perform steps for propagating, by a replication mechanism, changes to a data entry made by a data change source, the steps comprising:

first receiving, by the replication mechanism, a change to a data entry by the data change source;

building, from the change to the data entry, a data change object specifying a first change on an identified data construct;

rendering the data change object available for transmission to at least a data change destination; and

providing the data change object to the data change destination.

32. The computer-readable medium of claim 31 wherein the steps further comprise the step of:

combining the change with other changes within the data change object to render a net change object representing the combined changes.

33. The computer-readable medium of claim 31 wherein the building step comprises:

inserting, within the data change object, at least one action attribute specifying at least one action performed upon the identified data construct.

34. The computer-readable medium of claim 33 wherein the identified data construct is a multilevel object structure and wherein the inserting step comprises:

specifying a first action on the data change object at a first level of the data change object; and

specifying a second action on the data change object at a second level of the data change object.

35. The computer-readable medium of claim 31 wherein the steps further comprise the step of:

applying a filter to the change.

36. The computer-readable medium of claim 31 wherein the steps further comprise:

retrieving supplementary data; and

incorporating the supplementary data into the data change object.

37. The computer-readable medium of claim 36 wherein the steps further comprise:

synchronizing the change to the data entry and the supplementary data.

38. The computer-readable medium of claim 37 wherein the change to the data entry by the data change source occurs at a first time, T1, and the retrieving supplementary data step occurs at a subsequent time T3, and wherein the synchronizing step comprises:

correcting a synchronization inconsistency arising from a transaction executed at a time T2, occurring between the changes at T1 and T3, pertaining to the supplementary data.

39. The computer-readable medium of claim 38 wherein the synchronizing step further comprises:

reversing a change to the supplementary data arising from the transaction at time T2, and wherein the reversing a change step is performed prior to the rendering step.

40. The computer-readable medium of claim 38 wherein the rendering step is not performed until the server mechanism processes all changes having a potential impact upon the synchronization of the change to the data entry and the supplementary data.

41. The computer-readable medium of claim 40 wherein the rendering step is performed after processing all transactions committed to the database between T1 and T3.

42. The computer-readable medium of claim 38 wherein the synchronizing inconsistencies step further comprises the steps of:

placing the data change object in a queue of data change objects based upon execution order of data change transactions; and

de-queuing the data change object when the data change object is at the head of the queue and the correcting a synchronization inconsistency step is complete.

43. The computer-readable medium of claim 37 wherein the steps further comprise:

applying a first filter to data changes specified in the data change object prior to the synchronizing step; and

applying a second filter to unchanged data specified in the data change object subsequent to the synchronizing step.

44. The computer-readable medium of claim 31 wherein the steps further comprise:

creating a second data change object on a second identified data construct; and

synchronizing the changed data in the data change object and the second data change object.

45. The computer-readable medium of claim 44 wherein the first data change object and second data change object are of different types.

46. The computer-readable medium of claim 31 wherein the building step is performed in response to a notification mechanism activated by the data change source submitting the change to the data entry, thereby facilitating near-real time processing of changes.

47. The computer-readable medium of claim 31 wherein the data change object is specified using self-identifying data type descriptors.

48. The computer-readable medium of claim 31 wherein the steps further comprise:

transforming the change to the data entry by the data change source from a first data type to render a data change in a second data type; and

incorporating the data change in the second data type into the data change object.

49. The computer-readable medium of claim 31 wherein the steps further comprise:

reformatting the change to the data entry by the data change source from a first format to render a data change in a second format; and

incorporating the data change in the second format into the data change object.

50. The computer-readable medium of claim 31 wherein the change to the data entry by the data change source is associated with at least a second change within a single data change transaction, and wherein the building step is performed upon both the change and the second change as a single atomic work unit.

51. The computer-readable medium of claim 31 wherein the steps further comprise:

maintaining a set of data change store state variables to facilitate coordinating storing and retrieving of data change objects from a storage location.

52. The computer-readable medium of claim 51 wherein the rendering step comprises placing the data change object within a data change store that includes a net data change object associated with a period of transactions, and further comprising the step of freezing the period in response to a request to retrieve the data change objects associated with the period of transactions.

53. The computer-readable medium of claim 31 wherein the data change source corresponds to a first application and the data change destination corresponds to a second application.

54. The computer-readable medium of claim 31 wherein the identified data construct is an identified data object.

55. The computer-readable medium of claim 31 wherein the replication mechanism is incorporated into a data replication server.

56. The computer-readable medium of claim 31 wherein the data entry is associated with a database.

58. The data change system of claim 57 wherein the data change processor further includes a functional component for combining the change with other changes within the data change object to render a net change object representing the combined changes.

59. The data change system of claim 57 wherein the data change objects include multilevel object structures specifying a first action on the data change object at a first level of the data change object, and specifying a second action on the data change object at a second level of the data change object.

60. The data change system of claim 57 wherein the data change system incorporates configurable filtering functions.

61. The data change system of claim 60 wherein the filtering functions are facilitated by DLLs.

62. The data change system of claim 57 wherein the data change processor comprises a data change object buffer facilitating synchronizing the change to the data entry and supplementary data.

63. The data change system of claim 62 wherein the data change object buffer comprises a queue, and wherein the queue is managed within the data change processor to place the data change object in a queue of data change objects based upon execution order of data change transactions;

and de-queuing the data change object when the data change object is at the head of the queue and the incorporating step is complete.

64. The data change system of claim 62 wherein the data change processor comprises a multi-stage filter including:

a first filter stage for applying a first filter to data changes specified in the data change object prior to the synchronizing step; and

a second filter stage for applying a second filter to unchanged data specified in the data change object subsequent to the synchronizing step.

65. The data change system of claim 57 wherein the data change object is specified using self-identifying data type descriptors.

66. The data change system of claim 57 wherein the data change processor includes a postprocessor for transforming the change to the data entry by the data change source from a first data type to render a data change in a second data type, and incorporating the data change in the second data type into the data change object.

67. The data change system of claim 57 wherein the data change processor includes a postprocessor for reformatting the change to the data entry by the data change source from a first format to render a data change in a second format, and incorporating the data change in the second format into the data change object.

68. The data change system of claim 57 wherein the data change processor includes for a set of data change store state variables to facilitate coordinating storing and retrieving of data change objects from a storage location.

69. The data change system of claim 68 wherein the set of data change store state variables includes a freeze variable for freezing a period thereby foreclosing adding further data change objects, after a point corresponding to the freeze variable, to a set of changes associated with the period.

70. The data change system of claim 57 wherein the data change object includes:

a first tagged field identifying the object type for the identified data object; and

a second tagged field identifying a new value for the identified data object.

71. The data change system of claim 70 wherein the data change object includes:

a third tagged field identifying an action on the identified data object;

a fourth tagged field identifying an old value for the identified data object.

72. The data change system of claim 71 wherein the possible values for the third tagged field include values corresponding to inserting, updating and deleting at least a specified part of the identified data object.

73. The data change system of claim 57 wherein the data change source corresponds to a first application and the data change destination corresponds to a second application.

74. The data change system of claim 57 wherein the identified data construct is an identified data object.

75. The data change system of claim 57 wherein the data change processor is incorporated into a data replication server.

76. The data change system of claim 57 wherein the data entry is associated with a database.

57. A data change system for propagating changes to a data entry made by a data change source, the change server system comprising:

a data change input interface for first receiving a change to a data entry by the data change source;

a data change processor for building, from the change to the data entry, a data change object specifying a first change on an identified data construct, and rendering the data change object available for transmission to at least a data change destination; and

a data change object output interface for providing the data change object to the data change destination.