1. Relational Theory and Design
Unit 2

2. Key Concepts Relational model concepts
Entity Relationship Diagram (ERD) symbols
Primary keys
Foreign keys
Integrity rules
ERD design process
Cardinality
Data types

3. Terms Database (catalog) Row (record, tuple) Column (field, attribute)
Cell (field, data item)
Primary key

4. Entity Concepts Entity – type of item modeled in the database
Attribute – Values describing the entity
Relationship – Link between two tables

5. One-to-One
Relates one row in the parent to zero or one (or exactly one) in the child.
Each student has one locker.
Each locker is assigned to one student.

6. One-to-Many
Relates one row in the parent to zero or more rows (or one or more rows) in the child.
Each teacher teaches multiple classes.
Each class has one teacher.

7. Many-to-Many Multiple relationships exist between parent and child.
As associative table is used to track the relationships
Each student has multiple teachers.
Each teacher has multiple students.

8. Primary key Unique Minimal Not null Nonupdateable
Include Database Design and Development, Exhibit 2-6, page 19

9. Relationships
Database Design and Development, Exhibit 2-9, page 20

10. Data Integrity Entity integrity – identifies each row as unique
Referential integrity – Requires matched foreign key values.

11. First Normal Form
Database Design and Development, Exhibit 2-13, page 22

12. Database Systems
Hierarchical
Network
Relational
Object-oriented

13. Represent Entities as Tables
Entities are the items stored in the database
Most represent physical items such as persons and places
Start by identifying all possible entities

14. Determine Relationships
Database Systems, Figure 13.12, pg. 405

15. List Fields Fields, or attributes, describe entities.
Most entities will have several attributes.

16. Identify Keys Each table must have a primary key.
Primary key uniquely identfies row.
Must be unique, minimal, not null, and nonupdateable.
Related child table must have a foreign key

17. Determine Data Types Determine data type and size for each attribute
Primary and foreign keys must match in data type and size

18. Table
Database Design and Development, Exhibit 3-1.1, page 32

19. Relationship (none)
Database Design and Development, Exhibit 3-1.2

20. Fields
Database Design and Development, Exhibit 3-1.3

21. Keys
Database Design and Development, Exhibit 3-1.4

22. Data Types
Database Design and Development, Exhibit 3-1.5

23. Sample Data
Database Design and Development, Exhibit 3-3, page 33

24. Tables
Database Design and Development, Exhibit 3-4.1

25. Relationships
Database Design and Development, Exhibit 3-4.2

26. Fields
Database Design and Development, Exhibit 3-4.3

27. Keys
Database Design and Development, Exhibit 3-4.4

28. Data Types
Database Design and Development, Exhibit 3-4.5

29. Sample Data
Database Design and Development, Exhibit 3-6, Page 35

30. Tables
Database Design and Development, Exhibit 3-7.1, page 36

31. Relationships
Database Design and Development, Exhibit 3-7.2

32. Fields
Database Design and Development, Exhibit 3-7.3, page 37

33. Keys
Database Design and Development, Exhibit 3-7.4

34. Data Types
Database Design and Development, Exhibit 3-7.5

35. Acme Beer
Database Design and Development, Exhibit 3-13, page 48

36. Acme Beer Tables
Database Design and Development, Exhibit , page 49

37. Acme Beer Relationships
Database Design and Development, Exhibit

38. Acme Beer Fields
Database Design and Development, Exhibit

39. Acme Beer Keys
Database Design and Development, Exhibit

40. Acme Beer Data Types
Database Design and Development, Exhibit , page 50

41. Amazon Product Screens
Database Design and Development, Exhibit 3-17, page 54

42. Amazon Order Screen
Database Design and Development, Exhibit 3-18, page 54

43. Amazon ERD
Database Design and Development, Exhibit (only), page 56

44. Amazon Data
Database Design and Development, Exhibit 3-22