Occurrence management in product data management systems

1. A method for product data management, the method performed by a data processing system and comprising:

maintaining a data structure for a complex item, the data structure including a root node representing the complex item, at least one assembly node associated with the root node, and a plurality of part nodes each associated with the assembly node;

defining at least two absolute occurrences associated with the root node and corresponding to at least the root node and the assembly node, wherein each absolute occurrence is a unique path through the structure;

defining at least one managed occurrence that includes a plurality of the absolute occurrences; and

using the managed occurrence as a central control authority for the plurality of absolute occurrences.

2. The method of claim 1 , wherein a plurality of managed occurrences are defined, and the data processing system allows different managed occurrences and their respective absolute occurrences to be simultaneously manipulated by different users.

3. The method of claim 1 , wherein at least one of the absolute occurrences also corresponds to a part node.

4. The method of claim 1 , wherein the data processing system also displays a visual representation of a least a portion of the complex item to a user according to a selected one of the at least one managed occurrences.

5. The method of claim 1 , wherein using the managed occurrence as a central control authority includes performing access control, workflow, checkout, and release functions using the managed occurrence.

6. The method of claim 1 , wherein the complex item is a product, the assembly node represents an assembly of the product, and the part node represents an individual part of the assembly.

7. The method of claim 1 , wherein the context node has control over the managed occurrence.

8. A data processing system comprising:

a processor; and an accessible memory, the data processing system particularly configured to maintain a data structure for a complex item, the data structure including a root node representing the complex item, at least one assembly node associated with the root node, and a plurality of part nodes each associated with the assembly node;

define at least two absolute occurrences associated with the root node and corresponding to at least the root node and the assembly node, wherein each absolute occurrence is a unique path through the structure;

define at least one managed occurrence that includes a plurality of the absolute occurrences; and

use the managed occurrence as a central control authority for the plurality of absolute occurrences.

9. The data processing system of claim 8 , wherein a plurality of managed occurrences are defined, and the data processing system allows different managed occurrences and their respective absolute occurrences to be simultaneously manipulated by different users.

10. The data processing system of claim 8 , wherein at least one of the absolute occurrences also corresponds to a part node.

11. The data processing system of claim 8 , wherein the data processing system is also configured to display a visual representation of a least a portion of the complex item to a user according to a selected one of the at least one managed occurrences.

12. The data processing system of claim 8 , wherein using the managed occurrence as a central control authority includes performing access control, workflow, checkout, and release functions using the managed occurrence.

13. The data processing system of claim 8 , wherein the complex item is a product, the assembly node represents an assembly of the product, and the part node represents an individual part of the assembly.

14. The data processing system of claim 8 , wherein the context node has control over the managed occurrence.

15. A non-transitory computer-readable medium encoded with executable instructions that, when executed, cause one or more data processing systems to:

maintain a data structure for a complex item, the data structure including a root node representing the complex item, at least one assembly node associated with the root node, and a plurality of part nodes each associated with the assembly node;

define at least two absolute occurrences associated with the root node and corresponding to at least the root node and the assembly node, wherein each absolute occurrence is a unique path through the structure;

define at least one managed occurrence that includes a plurality of the absolute occurrences; and

use the managed occurrence as a central control authority for the plurality of absolute occurrences.

16. The computer-readable medium of claim 15 , wherein a plurality of managed occurrences are defined, and the instructions cause the data processing system to allow different managed occurrences and their respective absolute occurrences to be simultaneously manipulated by different users.

17. The computer-readable medium of claim 15 , wherein at least one of the absolute occurrences also corresponds to a part node.

18. The computer-readable medium of claim 15 , wherein the instructions cause the data processing system to display a visual representation of a least a portion of the complex item to a user according to a selected one of the at least one managed occurrences.

19. The computer-readable medium of claim 15 , wherein using the managed occurrence as a central control authority includes performing access control, workflow, checkout, and release functions using the managed occurrence.

20. The computer-readable medium of claim 15 , wherein the complex item is a product, the assembly node represents an assembly of the product, and the part node represents an individual part of the assembly.