1. 1 Agenda 01/13/05 Announcement Database Development Process (Chapter 2)

2. 2 Announcement A Quiz about Chapter 9 on Tuesday, 01/18/05 –Open book –Bring your database textbook (or a copy of chapter 9) to the class For your diagramming software, visit the following web site and download a RFlow trial version: http://graphicssoft.about.com/cs/diagramswpc

3. 3 Database Development Process (Chapter 2)

4. 4 “It is a capital mistake to theorize before one has data” Sherlock Holms’ remarks in A Scandal in Bohemia (Sir Conan Doyle, 1891)

5. 5 8 Underlying Principles of Systems Development 1. Get the Users Involved 2.Use a Problem-Solving Approach 3. Establish Phases and Activities 4.Establish Standards for Consistent Development and Documentation 5.Justify Systems as Capital Investments 6.Don’t Be Afraid to Cancel or Revise Scope 7. Divide and Conquer 8.Design Systems for Growth and Change

6. 6 Strategies for IS Development Top-Down  Proceeds from general to specific  Particular systems are designed working from a broad knowledge of the entire organizations information needs Bottom-Up  Proceeds from specific to general  Individual systems are designed from a detailed knowledge of a distinct application

7. 7 Information Systems Development Process Sources  Information systems planning (top-down)  User application requests (bottom-up) IS Development Approaches  Systems Development Life Cycle (SDLC)  Rapid Application Development (RAD) - Prototyping

8. 8 Information Systems Planning Process IS Development Projects (i.e. Database Development) IS Development Projects (i.e. Database Development) Organization Mission Business Assessment Organization Strategic Plan Current IT Architecture IS Strategic Plan New IT Architecture IS Operational Plan

9. 9 Systems Development Life Cycle (SDLC) 1. System Identification and Selection 2. Project Initiation and Planning 3. Analysis 4. Logical Design 5. Physical Design 6. Implementation 7. Maintenance

10. 10 System Identification and Selection Problem determination Understanding of the business situation Feasibility study Justification for the system Authorization to proceed Priority

11. 11 Project Initiation and Planning Scope of the project Project schedule Resource requirements Systems architecture Enterprise data model

12. 12 Analysis  System requirements (detailed)  Conceptual model

13. 13 Logical Design  Functional specification of system components (detailed)

14. 14 Physical Design  Technical specification of system components (detailed)

15. 15 Implementation  System installation Applications Documentation Training

16. 16 Maintenance System Monitoring Repairing Upgrade Support

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18. 18 Database Development Activities in the SDLC 1.Planning 2.Analysis 3.Logical Design 4.Physical Design 5.Implementation 6.Maintenance

19. 19 Planning  Examine the information systems architecture (blue print)  Review the enterprise data model Establish the general scope of the database

20. 20 Analysis Determine the specific data requirements for the system Create the conceptual data model: Entity-Relationship Diagram (ERD)

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23. 23 Logical Design Convert the data model to a database design: Relational Schema Perform quality control tuning on the logical database design - Integrity constraints -Normalized relations

24. 24 E-R Diagram HAS EXPENSE Relations (plus Relational SCHEMA) ACCOUNT (ACCOUNT_NO, ……) EXPENSE (EXPENSE_CODE, ACCOUNT_NO) Plus Constraints, Integrity Rules, Domain………. ACCOUNT

25. 25 Physical Design  Stipulate technical data specifications  Define the database design to the DBMS Construct data entry mechanisms

26. 26 Implementation  Load the data  Build the applications Produce documentation

27. 27 Maintenance  Tune the database for performance  Provide security and recovery Support the software and files

28. 28 Schema The conceptual organization of the entire database as viewed by stakeholders The structure that contains descriptions of objects created by a user such as tables, views and constraints

29. 29 Three Schema Architecture for Database Development Conceptual Schema  Analysis phase: E-R Diagram  Logical Design phase: Relational (Logical) Schema Internal Schema  Physical Design phase: DBMS Definition External Schema  Implementation phase: User Views

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31. 31 Components of Application Logic Involving Data Input / Output  Manage user input from the keyboard  Format and present output (screens and hardcopy) Processing  Data validation  Business rules  Data update  Data and information retrieval Storage  Performance  Security

32. 32 People in Database Development Systems analysts Programmers Database analysts Database and data administrators Systems programmers & network administrators Technical writers Users

33. 33 To Download RFFLOW Software Go to http://graphicssoft.about.com/cs/diagramswpc