1. Professor Michael J. Losacco CIS 1110 – Using Computers Database Management Chapter 9

2. Chapter9 2/29 Overview Define Database Describe Database Hierarchy Describe Database Functions Describe Validation Techniques List Features of Relational Databases Explain How to Use Queries

3. Chapter9 3/29 Database DBMS (Database Management System) Organized Collection of Data For Quick Access, Retrieval, & Use Database Software Allows You to Create Database Add, Change, & Delete Data Sort & Query Database Print Reports

4. Chapter9 4/29 Data & Information Processed Data Becomes Information Largest Commercial Database 2 PB — Yahoo (Oracle on Unix 2010)

5. Chapter9 5/29 Data & Information Data Integrity Degree to Which Data is Correct Database Contains Errors Loses Integrity GIGO (Garbage In, Garbage Out) Cannot Get Good Information From Bad Data

6. Chapter9 6/29 Database Hierarchy Database Contains Tables Table Contains Records Record Contains Fields Field Contains Characters

7. Chapter9 7/29 Database Hierarchy Field Combination of One or More Characters Smallest Unit of Data User Accesses Characteristics Name Uniquely Identifies Each Field Data Type Text Numeric Currency Size

8. Chapter9 8/29 Database Hierarchy Record Group of Related Fields Key Field AKA Primary Key Uniquely Identifies Each Record

9. Chapter9 9/29 Database Hierarchy Table Collection of Related Records Each Record Contains Same Fields Each Field Contains Different Data Database Group of Related Tables

10. Chapter9 10/29 Maintaining Data File Maintenance Procedure That Keeps Data Current Add Records When You Obtain New Data Change Records Correct Inaccurate Data Update Existing Data Delete Records Record No Longer Needed

11. Chapter9 11/29 Maintaining Data Validation Comparing Data with Set of Rules Reduce Data Entry Errors Enhance Data Integrity Types Alpha / Numeric Range Completeness Consistency

12. Chapter9 12/29 Features Data Dictionary Lists Fields For Each Table in Database Lists Properties For Each Field in Table

13. Chapter9 13/29 Features Form On Screen Window View Single Record Area to Enter / View / Change Data

14. Chapter9 14/29 Features Report Generator Creates Report Without User’s Knowledge of Programming

15. Chapter9 15/29 Features Report Types Detailed Summary Consolidates Data Exception Identifies Data Outside of Norm Conditions Define Status Range

16. Chapter9 16/29 Features Query Request Specific Data from Database SQL (Structured Query Language) Specify Data to Display, Print, or Store QBE (Query By Example) Retrieves Records that Match Criteria

17. Chapter9 17/29 Features Security Only Authorized Users Can Access Data Access Privileges Define Activities Group of Users Can Perform Read-only Privileges User Can View Data, But Cannot Change It Full-update Privileges User Can View & Change Data

18. Chapter9 18/29 Features Backup Copy of Entire Database Log Listing of Activities that Change Contents Places Three Items In Log Before Image Actual Change After Image

19. Chapter9 19/29 Features Log Example

20. Chapter9 20/29 Database Models Model Rules & Standards Defining: How Database Organizes Data How Users View Data Types Relational Object-oriented Multidimensional

21. Chapter9 21/29 Database Models Relational Stores Data in Tables Consist of Rows (Records) & Columns (Fields) Each Row has Primary Key Related Tables Must Have Common Field

22. Chapter9 22/29 Database Models Relational

23. Chapter9 23/29 Database Models Object-Oriented Stores Data in Objects Can Contain Both Data & Actions Advantages Can Store More Types of Data Can Access Data Faster Programmers Can Reuse Objects

24. Chapter9 24/29 Database Models Object-Oriented Examples Multimedia Images, Audio Clips, Video Clips CAD Engineering, Architectural, Scientific Data Groupware Schedules, Calendars, Memos, Reports Hypertext Links to Other Documents

25. Chapter9 25/29 Database Models Object-Oriented Example

26. Chapter9 26/29 Database Models Multidimensional Stores Data in More than Two Dimensions Allow Users to Analyze Any View of Data Advantages Consolidates Data Faster than Relational

27. Chapter9 27/29 Database Models Multidimensional Examples Data Warehouse Comprehensive Data Required to Analyze Data Across Enterprise From Multiple Databases

28. Chapter9 28/29 Database Models Multidimensional Examples Data Mining Find Patterns & Relationships Among Data Based on Open-ended User Queries Click Stream Every Action Visitors Take in Web Site

29. Chapter9 29/29 Database Development Process