1. Chapter 5
Database Processing

2. WHAT IS THE PURPOSE OF A DATABASE?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

3. What Is the Purpose of a Database?
Organize and keep track of things
Keep track of multiple themes
General rule:
Single theme store in a spreadsheet
Multiple themes require a database
Basic purpose of a database is to organize and keep track of things. Databases are needed when you need to keep track of multiple themes, such as grades, students, office visits and messages.
General rule:
Use a spreadsheet for lists of data involving single theme.
Use a database for data with multiple themes.

4. A List of Student Grades Presented in a Spreadsheet – Single Theme
Spreadsheet with a single theme – Grades.

5. Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Data Redundancy and Data Inconsistency
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

6. Student Data Form With Multiple Themes
Forms are difficult, if not impossible, to produce from a spreadsheet, but are easily produced with a database.

7. WHY DO WE NEED DATABASES
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

8. Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
Why we need databases
Size
Ease of Updating
Accuracy
Security
Redundancy
Importance
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

9. Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
WHAT IS A DATABASE?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

10. Components of a Database
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

11. Tables Table or file: A group of records
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

12. Tables (cont’d)
Each table must have a unique identifier called the Primary Key (PK)
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

13. Relational databases Relation More Special Terms
Relationships among tables are created by using foreign keys
Relation
Formal term for a table
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

14. Relationships Among Records
Database has multiple tables (one for each theme)
Values in one table may relate to records in other tables
Field(s) that uniquely identify a record in a table
Relational database
Primary or Unique key
Foreign key
Each table must have a key
A non-primary key in one table that is related to a primary key of a different table
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

15. Primary and Foreign Keys
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

16. Metadata Metadata Describes data by:
Database: Self-describing collection of integrated records
Metadata
Data that describes data
Makes databases more useful
Makes databases easier to use
Describes data by:
Data type: text, number, date, etc.
Field name
Field properties
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

17. Sample Metadata in Access
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

18. Features of Relational Databases
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

19. Features of Relational Databases (cont’d)
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

20. Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall
WHAT IS A DBMS?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

21. What Is a DBMS and What Does It Do?
Database management system (DBMS)
Program that creates, processes, and administers databases
Examples:
Database
Collection of tables, relationships, and metadata
DBMS
A software program
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

22. Components of a Database Application System
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

23. Processing the Database
Four DBMS operations
Read
Insert
Modify
Delete data
These operations are requested in applications that call upon the DBMS in different ways.

24. Structured Query Language (SQL)
SQL (see-quell)
International standard
Used by most popular DBMS
Structured Query Language (SQL) is used for processing the database. SQL is an international standard language for creating databases and database structures, and processing databases. SQL is used by all popular DBMS products.

25. Structured Query Language (SQL)
Structured Query Language (SQL) is used for processing the database. SQL is an international standard language for creating databases and database structures, and processing databases. SQL is used by all popular DBMS products.

26. WHAT IS A DATABASE APPLICATION?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

27. Database Applications
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

28. Forms, Reports, and Queries
Used to read, insert, modify, and delete data
Show data in structured context
May compute values such as Totals, within a report
Are a means of getting answers from database data
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

29. How Are Database Application Systems Developed?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

30. How Are Database Application Systems Developed?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

31. What Are the Components of the Entity-Relationship Data (ERD) Model?
Something users want to track
Order, customer, salesperson, item, volunteer, donation
Entities
Describe characteristics of an entity
OrderNumber, CustomerNumber, VolunteerName, PhoneNumber
Attributes
Attribute that uniquely identifies one entity instance from other instances
Student_ID_Number
Identifier
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

32. Creating ERDs
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

33. Student Data Model Entities
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

34. Example of Department, Adviser, and Student Entities and Relationships
A department may have many advisers
An adviser works in one department
An adviser advises many students
A student may have one or more advisers
1:N relationships
N:M relationships
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

35. Example of Department, Adviser, and Student Entities and Relationships
N:M
1:N
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

36. Entity Relationship Diagram (ERD) ― Version 1
Crow’s Feet
1:N
N:M
1:N = one-to-many relationships
One department can have many advisers, but an adviser is in only one department
N:M = many-to-many relationships
One adviser can have many students and one student can have many advisers
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

37. Entity Relationship Diagram (ERD) – Version 2
“Crow’s Foot”
N:M = many-to-many relationship
A department has many advisors and an advisor may advise for more than one department
1:N = one-to-many relationship
A student has only one advisor, but an adviser may advise many students
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

38. Defining one-to-many relationships
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

39. How Are Database Application Systems Developed?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

40. Transforming a Data Model into a Database Design
Represent each entity with a table
Entity identifier becomes table key
Entity attributes become table columns
Normalize tables as necessary
Represent relationships
Use foreign keys
Create additional tables for N:M relationships
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

41. Representing 1:N Relationships
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

42. Exploring many-to-many relationships
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

43. Representing an N:M Relationship: Strategy for Foreign Keys
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

44. How Are Database Application Systems Developed?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

45. What Is the Difference Between an Enterprise DBMS and a Personal DBMS?
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall

46. What Is the Difference Between an Enterprise DBMS and a Personal DBMS?
Processes large organizational and workgroup databases
Supports many users (thousands plus)
Examples: DB2, SQL Server, Oracle, MySQL
Personal DBMS
Designed for smaller, simpler database applications
Supports fewer than 100 users (mostly 1–10 users)
Examples: Access, dBase, FoxPro, R-Base
Copyright © 2012 Pearson Education, Inc. Publishing as Prentice Hall