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ER Diagram Participation - Exercise

Diagramming types of participation

Diagramming Relationships and Types of participation (course project exercise 3)

Objective: Complete an ER diagram for the Stories on CD case study.

Exercise Scoring

This exercise is worth a total of 60 points. You will receive up to five points for each correctly submitted piece of information according to the instructions below.

Background/overview

The preceding two lessons identified the constructs used to diagram relationship types between entities (1:1, 1:N, and M:N) and the symbols placed on the constructs to indicate mandatory and optional entity participation in the various relationships. In this exercise, you will use these symbols and constructs to create an ER diagram for the Stories on CD case study.

Instructions

Below are the five entities for Stories on CD, with attributes added.
five entities for Stories on CD
Five entities for Stories on CD

Next are five possible relationship constructs labeled A through E, with participation type included on the construct.
Five possible relationships
Five possible relationships

Your task, moving left to right through the Stories on CD entities, is to select the appropriate construct for each relationship. There are four relationships to consider:
  1. CUSTOMER:ORDER
  2. ORDER:LINE ITEM
  3. LINE ITEM:CD
  4. CD:DISTRIBUTOR

For each entity, you must also identify all key types for that relationship. Use the sample format below for your answers.
VENDOR:PRODUCT
Use construct D 
 
VENDOR: VendID=PK  
PRODUCT: ProdID=PK, VendID=FK

Hints

Do not forget about the CPK/FK key types.

Submitting your exercise

Type or paste your answers into the text box below, then click Submit to submit them and view a results page. You will receive a response as you submit the form.