Storing relationship tables identifying object relationships

• US 5,995,973 A
• Filed: 08/29/1997
• Issued: 11/30/1999
• Est. Priority Date: 08/29/1997
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Daudenarde, Jean-Jacques P.
• Primary Examiner(s): Lintz, Paul R.
• Assistant Examiner(s): Colbert, Ella
• Application Number:
  US08/921,198
• Time in Patent Office: 823 Days
• Field of Search: 707/2, 707/3, 707/4, 707/100, 707/102, 707/103, 364/282.1, 364/283.4, 395/680, 395/683
• US Class Current: 1/1
• CPC Class Codes: G06F 16/289 Object oriented databases
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure

Abstract

A method, apparatus, and article of manufacture for maintaining object relationships. A query is executed in a computer to retrieve data from a database stored on a data storage device. Initially, one or more relationship objects are created, wherein each relationship object identifies a source object and a related target object. Next, when accessing a source object, related target objects are determined using the relationship object. When accessing a target object, related source objects are determined using the relationship object.

Claims

1. A method of executing a query in a computer to retrieve data from a data base stored on a data storage device, comprising the steps of:

storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects;

creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects;

when accessing a source object, determining related target objects using the relationship object having a selected relationship; and

when accessing a target object, determining related source objects using the relationship object having a selected relationship.

2. The method of claim 1 above, wherein the relationship object is comprised of a header having an indicator linking the relationship object to the source object.

3. The method of claim 2 above, wherein the header has a direction flag indicating that the relationship object represents a direct relationship.

4. The method of claim 3 above, wherein the relationship elements correspond to target objects.

5. The method of claim 2 above, wherein the header has a direction flag indicating that the relationship object represents a reverse relationship.

6. The method of claim 5 above, wherein the relationship elements correspond to source objects.

7. The method of claim 1 above, further comprising the step of deleting a source object.

8. The method of claim 7 above, wherein the relationship object has an owner flag indicating that the source object owns the target object and wherein the step of deleting further comprises the step of deleting the target object.

9. The method of claim 7 above, wherein the relationship object has an owner flag indicating that the source object does not own the target object and wherein the step of deleting further comprises the step of setting an indicator to the source object to indicate that the source object has been deleted.

10. The method of claim 1 above, wherein the target object is transient.

11. The method of claim 1 above, wherein the target object is persistently stored.

12. The method of claim 1 above, wherein the source object is transient.

13. The method of claim 1 above, wherein the source object is persistently stored.

14. A method of executing a query in a computer to retrieve data from a database stored on a data storage device, comprising the steps of:

storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects;

creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects; and

when accessing a source object, determining related target objects using the relationship object having a selected relationship.

15. The method of claim 14 above, wherein the target object is transient.

16. The method of claim 14 above, wherein the target object is persistently stored.

17. The method of claim 14 above, wherein the source object is transient.

18. The method of claim 14 above, wherein the source object is persistently stored.

19. A method of executing a query in a computer to retrieve data from a database stored on a data storage device, comprising the steps of:

storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects;

creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identities a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects; and

when accessing a target object, determining related source objects using the relationship object having a selected relationship.

20. The method of claim 19 above, wherein the target object is transient.

21. The method of claim 19 above, wherein the target object is persistently stored.

22. The method of claim 19 above, wherein the source object is transient.

23. The method of claim 19 above, wherein the source object is persistently stored.

24. An apparatus for executing a query to retrieve data from a database, comprising:

a computer having a memory and a data storage device coupled thereto, wherein the data storage device stores the database;

one or more computer programs, performed by the computer, for storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects, creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects, when accessing a source object, determining related target objects using the relationship object having a selected relationship, and, when accessing a target object, determining related source objects using the relationship object having a selected relationship.

25. The apparatus of claim 24 above, wherein the relationship object is comprised of a header having an indicator linking the relationship object to the source object.

26. The apparatus of claim 25 above, wherein the header has a direction flag indicating that the relationship object represents a direct relationship.

27. The apparatus of claim 26 above, wherein the relationship elements correspond to target objects.

28. The apparatus of claim 25 above, wherein the header has a direction flag indicating that the relationship object represents a reverse relationship.

29. The apparatus of claim 28 above, wherein the relationship elements correspond to source objects.

30. The apparatus of claim 24 above, further comprising the means for deleting a source object.

31. The apparatus of claim 30 above, wherein the relationship object has an owner flag indicating that the source object owns the target object and wherein the means for deleting further comprise the means for deleting the target object.

32. The apparatus of claim 30 above, wherein the relationship object has an owner flag indicating that the source object does not own the target object and wherein the means for deleting further comprises the means for setting an indicator to the source object to indicate that the source object has been deleted.

33. The apparatus of claim 24 above, wherein the target object is transient.

34. The apparatus of claim 24 above, wherein the target object is persistently stored.

35. The apparatus of claim 24 above, wherein the source object is transient.

36. The apparatus of claim 24 above, wherein the source object is persistently stored.

37. An apparatus for executing a query to retrieve data from a database, comprising:

a computer having a memory and a data storage device coupled thereto, wherein the data storage device stores the database;

one or more computer programs performed by the computer, for storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects, creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects, and, when accessing a source object, determining related target objects using the relationship object having a selected relationship.

38. The apparatus of claim 37 above, wherein the target object is transient.

39. The apparatus of claim 37 above, wherein the target object is persistently stored.

40. The apparatus of claim 37 above, wherein the source object is transient.

41. The apparatus of claim 37 above, wherein the source object is persistently stored.

42. An apparatus for executing a query to retrieve data from a database, comprising:

a computer having a memory and a data storage device coupled thereto, wherein the data storage device stores the database;

one or more computer programs, performed by the computer, for storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects, creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects, and when accessing a target object, determining related source objects using the relationship object having a selected relationship.

43. The apparatus of claim 42 above, wherein the target object is transient.

44. The apparatus of claim 42 above, wherein the target object is persistently stored.

45. The apparatus of claim 42 above, wherein the source object is transient.

46. The apparatus of claim 42 above, wherein the source object is persistently stored.

47. An article of manufacture comprising a program storage medium readable a computer and embodying one or more instructions executable by the computer to perform method steps for executing a query to retrieve data from a database stored on a data storage device, the method comprising the steps of:

storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects;

creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects,

when accessing a source object, determining related target objects using the relationship object having a selected relationship; and

when accessing a target object, determining related source objects using the relationship object having a selected relationship.

48. The article of manufacture of claim 47 above, wherein the relationship object is comprised of a header having an indicator linking the relationship object to the source object.

49. The article of manufacture of claim 48 above, wherein the header has a direction flag indicating that the relationship object represents a direct relationship.

50. The article of manufacture of claim 49 above, wherein the relationship elements correspond to target objects.

51. The article of manufacture of claim 48 above, wherein the header has a direction flag indicating that the relationship object represents a reverse relationship.

52. The article of manufacture of claim 51 above, wherein the relationship elements correspond to source objects.

53. The article of manufacture of claim 47 above, further comprising the step of deleting a source object.

54. The article of manufacture of claim 53 above, wherein the relationship object has an owner flag indicating that the source object owns the target object and wherein the step of deleting further comprises the step of deleting the target object.

55. The article of manufacture of claim 53 above, wherein the relationship object has an owner flag indicating that the source object does not own the target object and wherein the step of deleting further comprises the step of setting an indicator to the source object to indicate that the source object has been deleted.

56. The article of manufacture of claim 47 above, wherein the target object is transient.

57. The article of manufacture of claim 47 above, wherein the target object is persistently stored.

58. The article of manufacture of claim 47 above, wherein the source object is transient.

59. The article of manufacture of claim 47 above, wherein the source object is persistently stored.

60. An article of manufacture comprising a program storage medium readable by a computer and embodying one or more instructions executable by the computer to perform method steps for executing a query to retrieve data from a database stored on a data storage device, the method comprising the steps of:

storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects;

creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects; and

when accessing a source object, determining related target objects using the relationship object having a selected relationship.

61. The article of manufacture of claim 60 above, wherein the target object is transient.

62. The article of manufacture of claim 60 above, wherein the target object is persistently stored.

63. The article of manufacture of claim 60 above, wherein the source object is transient.

64. The article of manufacture of claim 60 above, wherein the source object is persistently stored.

65. An article of manufacture comprising a program storage medium readable by a computer and embodying one or more instructions executable by the computer to perform method steps for executing a query to retrieve data from a database stored on a data storage device, the method comprising the steps of:

storing one or more relationship tables that identify relationships between source and target objects, wherein a relationship specifies one of a plurality of possible classifications between the source and target objects;

creating one or more relationship objects using the relationship tables, wherein each relationship object has multiple relationship elements, and wherein each relationship element identifies a source object and a related target object, and wherein each relationship object identifies a relationship specifying one of a plurality of possible classifications between the source and target objects; and

when accessing a target object, determining related source objects using the relationship object having a selected relationship.

66. The article of manufacture of claim 65 above, wherein the target object is transient.

67. The article of manufacture of claim 65 above, wherein the target object is persistently stored.

68. The article of manufacture of claim 65 above, wherein the source object is transient.

69. The article of manufacture of claim 65 above, wherein the source object is persistently stored.