1. Slide 1 Chapter 05 – Part 2 Data Modeling with the Entity-Relationship Model

2. Slide 2 Contents A. Sales Order Problem B. Solution

3. Slide 3 A. Sales Order Problem  A company want to computerize all data. The followings are reports:

4. Slide 4 Let’s design DB diagram for above requirements

5. Slide 5 B. Solution 1.Logical Analysis 2.Physical Analysis

6. Slide 6 1. Logical Analysis 1.1. First solution 1.2. Second solution 1.3. Identify Recursive Relationship

7. Slide 7 1.1. First solution 1.1.1. Identify Entity 1.1.2. Identify Attribute 1.1.3. Identify Weak Entity 1.1.4. Identify Primary Identifier 1.1.5. Identify Alternative Identifier 1.1.6. Identify Mandatory Attribute 1.1.7. Identify Relationship

8. Slide 8 1.1.1. Identify Entity

9. Slide 9 1.1.2. Identify Attribute

10. Slide 10 1.1.3. Identify Weak Entity 1.1.3.1. What is Weak Entity? 1.1.3.2. Design using ID-Dependent Entity

11. Slide 11 1.1.3.1. What is Weak Entity?  A weak entity is an entity whose existence depends upon another entity.  All ID-Dependent entities are considered weak.  An ID-dependent entity is an entity whose identifier includes the identifier of another entity.  But there are also non-ID-dependent weak entities.  The identifier of the parent does not appear in the identifier of the weak child entity.

12. Slide 12 1.1.3.2. Design using ID-Dependent Entity

13. Slide 13 1.1.4. Identify Primary Identifier

14. Slide 14 1.1.5. Identify Alternative Identifier

15. Slide 15 1.1.6. Identify Mandatory Attribute

16. Slide 16 1.1.7. Identify Relationship 1.1.7.1. Identify Maximum Cardinality 1.1.7.2. Identify Minimum Cardinality

17. Slide 17 1.1.7.1. Identify Maximum Cardinality

18. Slide 18 1.1.7.2. Identify Minimum Cardinality

19. Slide 19 1.2. Second solution 1.2.1. Identify Entity 1.2.2. Identify Attribute 1.2.3. Identify Primary Identifier 1.2.4. Identify Alternative Identifier 1.2.5. Identify Mandatory Attribute 1.2.6. Identify Relationship

20. Slide 20 1.2.1. Identify Entity

21. Slide 21 1.2.2. Identify Attribute

22. Slide 22 1.2.3. Identify Primary Identifier

23. Slide 23 1.2.4. Identify Alternative Identifier

24. Slide 24 1.2.5. Identify Mandatory Attribute

25. Slide 25 1.2.6. Identify Relationship 1.2.6.1. Identify Maximum Cardinality 1.2.6.2. Identify Minimum Cardinality

26. Slide 26 1.2.6.1 Maximum Cardinality on Diagram

27. Slide 27 1.2.6.2. Minimum Cardinality on Diagram

28. Slide 28 1.3. Identify Recursive Relationship 1.3.1. What is Recursive Relationship? 1.3.2. Recursive Relationship on Diagram

29. Slide 29 1.3.1. What is Recursive Relationship?  A recursive relationship occurs when an entity has a relationship to itself.  There are three types of Recursive Relationships:  1: 1  1:N  N:M

30. Slide 30 1.3.2. Recursive Relationship on Diagram

31. Slide 31 2. Physical Diagram

32. Slide 32