Database system having heterogeneous object types

• US 20030110179A1
• Filed: 12/10/2001
• Published: 06/12/2003
• Est. Priority Date: 12/10/2001
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle Corporation
• Inventors: Barton, Lee B.
• Granted Patent: US 7,124,140 B2
• Time in Patent Office: Days
• US Class Current: 707/101
• CPC Class Codes: G06F 16/24 Querying
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation
• 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
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A method for extracting metadata for plural related objects of different types from a database includes defining a heterogeneous object type as a collection of database objects of different types. Upon a request to fetch a particular heterogeneous object, member objects of the heterogeneous object are fetched from the particular heterogeneous object in a specific order based on the definition of the heterogeneous object'"'"'s type, such as a valid order for re-creating the particular heterogeneous object. The set of member objects to be fetched can be restricted according to at least one specified filter, which itself may be translated into a second filter according to a type of a member object being fetched. Such translated filters can inherit values from the filter specified in the request for the particular heterogeneous object type, or can have a fixed value of some data type. The extracted metadata can be formatted to recreate the particular heterogeneous object.

Claims

1. A method for extracting metadata for plural related objects of different types from a database, comprising:

defining a heterogeneous object type as a collection of database objects of different types; and

upon a request to fetch a particular heterogeneous object, fetching member objects from the particular heterogeneous object in a specific order based on the definition of the heterogeneous object'"'"'s type.

2. The method of claim 1, wherein the specific order is a valid order for re-creating the particular heterogeneous object.

3. The method of claim 1, wherein a heterogeneous object type is a table export type.

4. The method of claim 1, wherein an heterogeneous object type is a database export type.

5. The method of claim 1, wherein an heterogeneous object type is a schema export type.

6. The method of claim 1, wherein an heterogeneous object type is a tablespace export type.

7. The method of claim 1, wherein a heterogeneous object type includes another heterogeneous object type.

8. The method of claim 1, further comprising:

restricting a set of member objects to be fetched according to at least one specified filter.

9. The method of claim 8, wherein the at least one specified filter is translated to a second filter according to a type of a member object being fetched.

10. The method of claim 1, further comprising:

specifying, in a first table, heterogeneous object types;

defining, in a second table, the specific order in which member types for a given heterogeneous object type are to be returned; and

upon a fetch command, fetching member objects according to the specific order defined in the second table.

11. The method of claim 10, further comprising:

specifying, in a third table, filters that can be applied to the particular heterogeneous object type.

12. The method of claim 11, further comprising:

specifying, in a fourth table, filter translations for individual member object types.

13. The method of claim 12, wherein a translated filter inherits a filter value from a filter specified for the particular heterogeneous object type.

14. The method of claim 12, wherein a filter defined in the fourth table has a fixed text value.

15. The method of claim 12, wherein a filter defined in the fourth table has a fixed boolean value.

16. The method of claim 1, further comprising:

returning the metadata in a formatted markup language.

17. The method of claim 16, wherein the formatted markup language is XML.

18. The method of claim 16, further comprising:

translating the markup language-formatted data into statements formatted to recreate the particular heterogeneous object.

19. A method for retrieving, from a relational database, object metadata, comprising:

receiving a single request for metadata for a logical unit within the database, the logical unit comprising plural objects of different types;

extracting the requested metadata; and

returning the extracted metadata in an order in which the logical unit can be recreated.

20. The method of claim 19, wherein the logical unit comprises a table and its dependent objects.

21. The method of claim 20, wherein a dependent object is a constraint.

22. The method of claim 20, wherein a dependent object is an index.

23. The method of claim 20, wherein a dependent object is a grant.

24. The method of claim 19, wherein the logical unit comprises all objects in a schema.

25. The method of claim 19, wherein the logical unit comprises all objects in the database.

26. The method of claim 19, further comprising:

using the extracted metadata to recreate the logical unit of objects on another database.

27. The method of claim 19, wherein the request specifies at least one heterogeneous object type filter, the method further comprising:

restricting objects to be extracted based on the at least one heterogeneous object type filter.

28. The method of claim 27, further comprising:

translating the heterogeneous object type filter to a member object filter for a member object type; and

restricting member objects of the member object type based on the member object filter.

29. The method of claim 28, wherein the member object filter value is inherited from the heterogeneous object type filter.

30. The method of claim 28, further comprising:

specifying the member object filter value as a fixed value.

31. The method of claim 30, wherein the fixed value is a boolean value.

32. The method of claim 30, wherein the fixed value is a text value.

33. The method of claim 19, wherein the single request comprises a single OPEN command, a single CLOSE command, and at least one FETCH command.

34. A database in which plural related objects of different types are defined, comprising:

a definition of at least one heterogeneous object type as a collection of member database objects of different types; and

an order specification for fetching member object types of the at least one heterogeneous object type in a specified order.

35. The database of claim 34, wherein the specified order is a valid order for recreating the particular heterogeneous object.

36. The database of claim 34, wherein a heterogeneous object type is a table export type.

37. The database of claim 34, wherein a heterogeneous object type is a database export type.

38. The database of claim 34, wherein a heterogeneous object type is a schema export type.

39. The database of claim 34, wherein a heterogeneous object type is a tablespace export type.

40. The database of claim 34, wherein a heterogeneous object type includes another heterogeneous object type.

41. The database of claim 34, further comprising:

a filter associated with a heterogeneous object type, a set of member objects of said heterogeneous object type to be fetched being restricted according to the filter.

42. The database of claim 41, further comprising:

a filter translator which translates the at least one specified filter to a second filter according to a type of a member object being fetched.

43. The database of claim 34, further comprising:

a first table which specifies heterogeneous object types; and

a second table which specifies the order in which member types for a given heterogeneous object type are to be returned.

44. The database of claim 43, further comprising:

a third table which specifies filters that can be applied to the particular heterogeneous object type.

45. The database of claim 44, further comprising:

a fourth table which provides filter translations for individual member object types.

46. The database of claim 45, wherein a translated filter inherits a filter value from a filter specified for the particular heterogeneous object type.

47. The database of claim 45, wherein a filter defined in the fourth table has a fixed text value.

48. The database of claim 45, wherein a filter defined in the fourth table has a fixed boolean value.

49. The database of claim 34, further comprising:

the metadata is returned in a formatted markup language.

50. The database of claim 49, wherein the formatted markup language is XML.

51. The database of claim 49, further comprising:

a translator which translates the markup language-formatted data into statements formatted to recreate the particular heterogeneous object.

52. A database for storing data for retrieval, comprising:

an interface which receives a single request for metadata for a logical unit within the database, the logical unit comprising plural objects of different types;

an extractor which extracts the requested metadata; and

a formatter which formats and returns the extracted metadata in a specified order.

53. The database of claim 52, where the specified order is an order in which the logical unit can be recreated.

54. The database of claim 52, wherein the logical unit comprises a table and its dependent objects.

55. The database of claim 54, wherein a dependent object is a constraint.

56. The database of claim 54, wherein a dependent object is an index.

57. The database of claim 54, wherein a dependent object is a grant.

58. The database of claim 52, wherein the logical unit comprises all objects in a schema.

59. The database of claim 52, wherein the logical unit comprises all objects in the database.

60. The database of claim 52, wherein the extracted metadata is used to recreate the logical unit of objects on another database.

61. The database of claim 52, wherein the extractor is restricted to objects based on a heterogeneous object type filter specified in the request.

62. The database of claim 61, further comprising:

a filter translator which translates the heterogeneous object type filter to a member object filter associated with a member object type, the extractor being restricted to member objects of the member object type based on the member object filter.

63. The database of claim 62, wherein the member object filter value is inherited from the heterogeneous object type filter.

64. The database of claim 62, wherein the member object filter value is specified as a fixed value.

65. The database of claim 64, wherein the fixed value is a boolean value.

66. The database of claim 64, wherein the fixed value is a text value.

67. The database of claim 52, wherein the single request comprises a single OPEN command, a single CLOSE command, and at least one FETCH command.

68. A computer program product for extracting metadata for plural related objects of different types from a database, the computer program product comprising a computer usable medium having computer readable code thereon, including program code which:

defines a heterogeneous object type as a collection of database objects of different types; and

upon a request to fetch a particular heterogeneous object, fetches member objects from the particular heterogeneous object in a specific order based on the definition of the heterogeneous object'"'"'s type.

69. A computer program product for retrieving, from a relational database, object metadata, the computer program product comprising a computer usable medium having computer readable code thereon, including program code which:

receives a single request for metadata for a logical unit within the database, the logical unit comprising plural objects of different types;

extracts the requested metadata; and

returns the extracted metadata in an order in which the logical unit can be recreated.