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# Resolving many-to-many Relationships - Exercise

Objective: Convert a many-to-many relationship into two "one-to-many" relationships.

## Exercise Scoring

This exercise is worth a total of 30 points. You will receive up to 10 points for correctly creating each attribute of the composite entity as described below.

## Background and Overview

In the preceding lesson, you learned that many-to-many relationships are resolved by breaking down each M:N relationship into two 1:N relationships. This is achieved by creating a composite entity whose only function is to represent the link between the other two entities. You also learned that the composite entity has no key attribute of its own; rather, it accepts the key attributes from the other two entities to form a composite key attribute.

### Instructions

The Stories on CD case study has one many-to-many relationship: the ORDER:CD relationship. Your task is to resolve the ORDER:CD relationship. The two entities are illustrated below, complete with the attributes you will need to complete this exercise.

Please name the composite entity you create LINE ITEM. Your answer should be in the following format:
 ORDER attributeattributeetc.

 LINE ITEM attributeattributeetc.

 CD attributeattributeetc.

### Hints

When a composite entity is created to link two other entities, it sometimes makes sense to move some non-key attributes out of the other two entities and into the composite entity. Keep this in mind when you populate the composite entity with attributes.