![© 2001
9Chapter 2
Figure 2-1 Segment from enterprise data model (Pine
Valley Furniture Company) [simplified E-R diagram,
repeat of figure 1.3]
Enterprise data model describes
the entities in an organization
and the relationship between
these entities](https://image.slidesharecdn.com/chap02r-170713031059/85/The-Database-Environment-Chapter-2-9-320.jpg)
The Database Environment Chapter 2
- 1. 1 Chapter 2:Chapter 2: The Database DevelopmentThe Database Development ProcessProcess Modern Database Management 6th Edition Jeffrey A. Hoffer, Mary B. Prescott, Fred R. McFadden
- 2. © 2001 2Chapter 2 Information Systems ArchitectureInformation Systems Architecture (ISA)(ISA) Overall blueprint for organization’s information systems Consists of: – Data (Enterprise Data Model – simplified ER Diagram) – Processes – data flow diagrams, process decomposition, etc. – Data Network – topology diagram (like fig 1.8) – People – people management using project management tools (Gantt charts, etc.) – Events and Points in Time (when processes are performed) – Reasons for events and rules (e.g. decision tables)
- 3. © 2001 3Chapter 2 Information EngineeringInformation Engineering A data-oriented methodology to create and maintain information systems Top-down planning approach. Four steps: – Planning Results in an Information Systems Architecture – Analysis Results in functional specifications…i.e. what we want – Design Results in design specifications…i.e. how we’ll do it – Implementation Results in final operational system
- 4. © 2001 4Chapter 2 Information Systems PlanningInformation Systems Planning Strategy development – IT Planning to meet Corporate strategy Three steps: 1. Identify strategic planning factors 2. Identify corporate planning objects 3. Develop enterprise model
- 5. © 2001 5Chapter 2 Identify Strategic PlanningIdentify Strategic Planning Factors (table 2.1)Factors (table 2.1) Organization goals – what we hope to accomplish Critical success factors – what MUST work in order for us to survive Problem areas – weaknesses we now have
- 6. © 2001 6Chapter 2 Identify Corporate PlanningIdentify Corporate Planning Objects (table 2.3)Objects (table 2.3) Organizational units Organizational locations Business functions – these might become the users Entity types – the things we are trying to model Information (application) systems
- 7. © 2001 7Chapter 2 Develop Enterprise ModelDevelop Enterprise Model Decomposition of business functions – See figure 2.2 Enterprise data model – See figure 2.1 Planning matrixes – See figure 2.3
- 8. © 2001 8Chapter 2 Enterprise Data ModelEnterprise Data Model First step in database development Specifies scope and general content Overall picture of organizational data, not specific design Entity-relationship diagram Descriptions of entity types Relationships between entities Business rules
- 9. © 2001 9Chapter 2 Figure 2-1 Segment from enterprise data model (Pine Valley Furniture Company) [simplified E-R diagram, repeat of figure 1.3] Enterprise data model describes the entities in an organization and the relationship between these entities
- 10. © 2001 10Chapter 2 Figure 2.2 -- Example of process decomposition of an order fulfillment function (Pine Valley Furniture) Decomposition -- breaking large tasks into smaller tasks in a hierarchical structure chart
- 11. © 2001 11Chapter 2 Planning MatrixesPlanning Matrixes Function-to-data entity Location-to-function Unit-to-function IS-to-data entity Supporting function-to-data entity – which data are captured, used, updated, deleted within each function IS-to-business objective
- 12. © 2001 12Chapter 2 Example business function-to-Example business function-to- data entity matrix (fig. 2.3)data entity matrix (fig. 2.3) Business Planning X X X X Product Development X X X X Materials Management X X X X X X Order Fulfillment X X X X X X X X X Order Shipment X X X X X X Sales Summarization X X X X X Production Operations X X X X X X X Finance and Accounting X X X X X X X X Customer Product RawMaterial Order WorkCenter WorkOrder Invoice Equipment Employee Business Function (users) Data Entity Types
- 13. © 2001 13Chapter 2 Alternative Approaches toAlternative Approaches to Database and IS DevelopmentDatabase and IS Development SDLC – System Development Life cycle – Detailed, well-planned development process – Time-consuming, but comprehensive – Long development cycle Prototyping – Rapid application development (RAD) – Cursory attempt at conceptual data modeling. – Define database during development of initial prototype. – Repeat implementation and maintenance activities with new prototype versions.
- 14. © 2001 14Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design
- 15. © 2001 15Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose --preliminary understanding Deliverable –request for project Database activity – enterprise modeling
- 16. © 2001 16Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose – state business situation and solution Deliverable – request for analysis Database activity – conceptual data modeling
- 17. © 2001 17Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose –thorough analysis Deliverable – functional system specifications Database activity – conceptual data modeling
- 18. © 2001 18Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose –information requirements structure Deliverable – detailed design specifications Database activity – logical database design
- 19. © 2001 19Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose –develop technology specs Deliverable – program/data structures, technology purchases, organization redesigns Database activity – physical database design
- 20. © 2001 20Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose –programming, testing, training, installation, documenting Deliverable – operational programs, documentation, training materials Database activity – database implementation
- 21. © 2001 21Chapter 2 Systems Development Life CycleSystems Development Life Cycle (figures 2.4, 2.5)(figures 2.4, 2.5) Project Identification and Selection Project Initiation and Planning Analysis Physical Design Implementation Maintenance Logical Design Purpose –monitor, repair, enhance Deliverable – periodic audits Database activity – database maintenance
- 22. © 2001 22Chapter 2 Figure 2-6 The prototyping methodology and database development process
- 23. © 2001 23Chapter 2 Figure 2-6 The prototyping methodology and database development process
- 24. © 2001 24Chapter 2 Figure 2-6 The prototyping methodology and database development process
- 25. © 2001 25Chapter 2 Figure 2-6 The prototyping methodology and database development process
- 26. © 2001 26Chapter 2 Figure 2-6 The prototyping methodology and database development process
- 27. © 2001 27Chapter 2 Managing Projects:Managing Projects: People InvolvedPeople Involved Systems analysts Database analysts Users Programmers Database/data administrators Systems programmers, network administrators, testers, technical writers
- 28. © 2001 28Chapter 2 Figure 2-7a Gantt Chart Shows time estimates of tasks
- 29. © 2001 29Chapter 2 Figure 2-7b PERT chart Shows dependencies between tasks
- 30. © 2001 30Chapter 2 Database SchemaDatabase Schema Physical Schema – Physical structures – covered in chapters 5 and 6 Conceptual Schema – ER models – covered in chapters 3 and 4 External Schema – User Views – Subsets of Conceptual Schema – Can be determined from business-function/data entity matrices – DBA determines schema for different users – This is part of people-management in databases
- 31. © 2001 31Chapter 2 Figure 2-8 Three-schema database architecture External schema Different people have different views of the database…these are the external schema Internal schema
- 32. © 2001 32Chapter 2 Figure 2-10 Three-tiered client/server database architecture
- 33. © 2001 33Chapter 2 Pine Valley FurniturePine Valley Furniture Preliminary data model (figure 2-11)
- 34. © 2001 34Chapter 2 Pine Valley FurniturePine Valley Furniture MS Access data model prototype (figure 2-14)