Method and system for an object model with embedded metadata and mapping information

• US 6,996,566 B1
• Filed: 11/21/2000
• Issued: 02/07/2006
• Est. Priority Date: 11/21/2000
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: George, Joseph Mulavelil, Krychniak, Piotr
• Primary Examiner(s): ROBINSON, GRETA LEE
• Application Number:
  US09/717,809
• Time in Patent Office: 1,904 Days
• Field of Search: 707/103.R, 707/100, 707/103.Y, 707/103.Z
• US Class Current: 1/1
• CPC Class Codes: G06F 16/289 Object oriented databases
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure

Abstract

Metadata is obtained from a database and provided to an object model that uses the database for persisting the state of its objects. The metadata provides the object model with constraints, size limits, or other limiting information about a database so that the object model can anticipate and handle potential errors that could occur at the database level. Rather than keeping the metadata embedded within the database, the object model obtains access to the metadata and can adopt policies for dealing with those constraints and limits. In addition, the object model is also provided with heuristics that can be applied to storage processing of attributes. In this manner, the object model becomes metadata-aware and can handle database operations more intelligently and thus propagate fewer errors to the client.

Claims

1. A method for storing object attribute data in a database, the method comprising the steps of:

retrieving metadata from the database, wherein the metadata indicates database limitations;

retrieving semantic information from a mapping repository, wherein the semantic information indicates a manner in which object attribute data is stored in the database; and

storing object attribute data in the database according to the semantic information and the metadata.

2. The method of claim 1 wherein the database limitations are selected from a group comprising record constraints, field constraints, and/or size limits.

3. The method of claim 1 further comprising:

storing the metadata using markup language to identify the metadata.

4. The method of claim 1 wherein the semantic information provides a mapping between object attributes and records in a relational database.

5. The method of claim 1 further comprising:

storing the semantic information using markup language to identify the semantic information.

6. The method of claim 1 further comprising:

determining whether or not the object attribute data has characteristics that conflict with the database limitations indicated within the retrieved metadata; and

in response to a determination that the object attribute data has characteristics that conflict with the database limitations, modifying the object attribute data so that the object attribute data does not have characteristics that conflict with the database limitations.

7. The method of claim 1 comprising:

retrieving heuristic information; and

modifying the object attribute data in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations.

8. The method of claim 1 wherein the metadata and the semantic information are retrieved during an initialization phase of an object model that uses the metadata on behalf of a client of the object model.

9. The method of claim 1 comprising:

retrieving heuristic information, wherein the heuristic information and the metadata are cached within an object model; and

modifying the object attribute data within the object model on behalf of a client in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations such that the modified object attribute data can be stored into the database without error.

10. A method for storing object attribute data in a database, the method comprising the steps of:

retrieving metadata from the database, wherein the metadata indicates database limitations;

retrieving semantic information from a mapping repository, wherein the semantic information indicates a manner in which object attribute data is stored in the database;

retrieving heuristic information, wherein the heuristic information and the metadata are cached within an object model;

modifying the object attribute data within the object model on behalf of a client in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations; and

storing the modified object attribute data in the database.

11. An apparatus for storing object attribute data in a database, the apparatus comprising:

first retrieving means for retrieving metadata from the database, wherein the metadata indicates database limitations;

second retrieving means for retrieving semantic information from a mapping repository, wherein the semantic information indicates a manner in which object attribute data is stored in the database; and

storing means for storing object attribute data in the database according to the semantic information and the metadata.

12. The apparatus of claim 11 wherein the database limitations are selected from a group comprising record constraints, field constraints, and/or size limits.

13. The apparatus of claim 11 further comprising:

storing the metadata using markup language to identify the metadata.

14. The apparatus of claim 11 wherein the semantic information provides a mapping between object attributes and records in a relational database.

15. The apparatus of claim 11 further comprising:

storing the semantic information using markup language to identify the semantic information.

16. The apparatus of claim 11 further comprising:

determining means for determining whether or not the object attribute data has characteristics that conflict with the database limitations indicated within the retrieved metadata; and

first modifying means for modifying, in response to a determination that the object attribute data has characteristics that conflict with the database limitations, the object attribute data so that the object attribute data does not have characteristics that conflict with the database limitations.

17. The apparatus of claim 11 comprising:

third retrieving means for retrieving heuristic information; and

second modifying means for modifying the object attribute data in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations.

18. The apparatus of claim 11 wherein the metadata and the semantic information are retrieved during an initialization phase of an object model that uses the metadata on behalf of a client of the object model.

19. The apparatus of claim 11 comprising:

retrieving means for retrieving heuristic information, wherein the heuristic information and the metadata are cached within an object model; and

modifying means for modifying the object attribute data within the object model on behalf of a client in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations such that the modified object attribute data can be stored into the database without error.

20. A computer program product in a computer readable medium for use in a data processing system for storing object attribute data in a database, the computer program product comprising:

instructions for retrieving metadata from the database, wherein the metadata indicates database limitations;

instructions for retrieving semantic information from a mapping repository, wherein the semantic information indicates a manner in which object attribute data is stored in the database; and

instructions for storing object attribute data in the database according to the semantic information and the metadata.

21. The computer program product of claim 20 wherein the database limitations are selected from a group comprising record constraints, field constraints, and/or size limits.

22. The computer program product of claim 20 wherein the semantic information provides a mapping between object attributes and records in a relational database.

23. The computer program product of claim 20 further comprising:

instructions for determining whether or not the object attribute data has characteristics that conflict with the database limitations indicated within the retrieved metadata; and

instructions for modifying, in response to a determination that the object attribute data has characteristics that conflict with the database limitations, the object attribute data so that the object attribute data does not have characteristics that conflict with the database limitations.

24. The computer program product of claim 20 comprising:

instructions for retrieving heuristic information; and

instructions for modifying the object attribute data in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations.

25. The computer program product of claim 20 wherein the metadata and the semantic information are retrieved during an initialization phase of an object model that uses the metadata on behalf of a client of the object model.

26. The computer program product of claim 20 comprising:

instructions for retrieving heuristic information, wherein the heuristic information and the metadata are cached within an object model; and

instructions for modifying the object attribute data within the object model on behalf of a client in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations such that the modified object attribute data can be stored into the database without error.

27. A computer program product in a computer readable medium for use in a data processing system for storing object attribute data in a database, the computer program product comprising:

instructions for retrieving metadata from the database, wherein the metadata indicates database limitations;

instructions for retrieving semantic information from a mapping repository, wherein the semantic information indicates a manner in which object attribute data is stored in the database;

instructions for retrieving heuristic information, wherein the heuristic information and the metadata are cached within an object model;

instructions for modifying the object attribute data within the object model on behalf of a client in accordance with the heuristic information if the object attribute data has characteristics that conflict with the database limitations; and

instructions for storing the modified object attribute data in the database.