What is the best way to create derived properties

Posted by user342788 on Stack Overflow See other posts from Stack Overflow or by user342788
Published on 2010-05-17T06:13:08Z Indexed on 2010/05/17 6:20 UTC
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objective-c

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core-data

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iphone-sdk

I have a datamodel with to-many to-many relations. Using the example of employee database let say the entity division is related to department which in turn is related to employee. The employee has an attribute salary. How best to have a attribute at the level of division which is derived from the salary attribute. For example average salary or maximum salary.

I would need those attributes to sort the list of departments.

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