iphone - Implement multiple relationship using core data -

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the er diagram

here above shows er-diagram.

it's easy implement to-many binary relationship using core data. confuse me how implement kind of multiple relationship.

hope give hand.

i not sure if understood problem correctly, wouldn't 2 one-to-many relationships (from course ta , student ta) describe model? each ta has 1 student , 1 course, each student , each course can related many tas.

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