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Chapter 5 – Part 2

Chapter 5 – Part 2. Data Modelling with the Entity-Relationship Model. Contents. A. Sales Order Problem B. Solution. A. Sales Order Problem. A company want to computerize all data. The followings are reports:. Let’s design DB diagram for above requirements. B. Solutions.

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Chapter 5 – Part 2

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  1. Chapter 5 – Part 2 Data Modelling with the Entity-Relationship Model

  2. Contents A. Sales Order Problem B. Solution

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

  4. Let’s design DB diagram for above requirements

  5. B. Solutions • Logical Analysis • Physical Analysis

  6. 1. Logical Analysis 1.1. None Experience 1.2. Experience 1.3. Identify Recursive Relationships

  7. 1.1. None Experience 1.1.1. Indentify Entity 1.1.2. Indentify Attributes 1.1.3. Identify Week Entities 1.1.4. Identify Primary Identifier 1.1.5. Identify Alternative Identifier 1.1.6. Identify Mandatory Attributes 1.1.7. Identify Relationship

  8. 1.1.1. Indentify Entity

  9. 1.1.2. Indentify Attributes

  10. 1.1.3. Identify Week Entities 1.1.3.1. What is week entities? 1.1.3.2. Design using ID-Dependent

  11. 1.1.3.1. What is week entities? • 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. 1.1.3.2. Design using ID-Dependent

  13. 1.1.4. Identify Primary Identifier

  14. 1.1.5. Identify Alternative Identifier

  15. 1.1.6. Identify Mandatory Attributes

  16. 1.1.7. Identify Relationship 1.1.7.1. Identify Maximum Cardinalities 1.1.7.2. Identify Minimum Cardinalities

  17. 1.1.7.1. Identify Maximum Cardinalities

  18. 1.1.7.2. Identify Minimum Cardinalities

  19. 1.1.7.2. Identify Minimum Cardinalities

  20. 1.1.7.2. Identify Minimum Cardinalities

  21. 1.1.7.1. Identify Maximum Cardinalities

  22. 1.2. Experience 1.2.1. Indentify Entity 1.2.2. Indentify Attributes 1.2.3. Identify Primary Identifier 1.2.4. Identify Alternative Identifier 1.2.5. Identify Mandatory Attributes 1.2.6. Identify Relationship

  23. 1.2.1. Indentify Entity

  24. 1.2.2. Indentify Attributes

  25. 1.2.3. Identify Primary Identifier

  26. 1.2.4. Identify Alternative Identifier

  27. 1.2.5. Identify Mandatory Attributes

  28. 1.2.6. Identify Relationship 1.2.6.1. Identify Maximum Cardinalities 1.2.6.2. Identify Minimum Cardinalities

  29. 1.2.6.1 Maximum Cardinalities on Diagram

  30. 1.2.6.2. Minimum Cardinalities on Diagram

  31. 1.3. Identify Recursive Relationships 1.3.1. What is Recursive Relationships ? 1.3.2. Recursive Relationships on Diagram

  32. 1.3.1. What is Recursive Relationships? • 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

  33. 1.3.2. Weak Entity on Diagram

  34. 2. Physical Diagram

  35. ?

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