Nov 22, 2013

ALL STUDENTS (READ ME)

All students are encouraged to write the at least 5 things they learned in a week on my class.

Nov 16, 2013

CHAPTER II

Enterprise Data Model

First step in database development
Specifies scope and general content
Overall picture of organizational data at high level of abstraction
Entity-relationship diagram
Descriptions of entity types
Relationships between entities
Business rules
Enterprise data model describes the high-level entities in an organization and the relationship between these entities
Information Systems Architecture
(ISA)
Conceptual blueprint for organization’s desired information systems structure
Consists of:
Data (e.g. Enterprise Data Model – simplified ER Diagram)
Processes – data flow diagrams, process decomposition, etc.
Data Network – topology diagram (like fig 1.9)
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)

Information Engineering

A data-oriented methodology to create and maintain information systems
Top-down planning: a generic IS planning methodology  for obtaining a broad understanding of the IS needed by the entire organization
Four steps to Top-Down planning:
Planning
Analysis
Design
Implementation
Information Systems Planning

Purpose: align information technology with organization’s business strategies
Three steps:
1.Identify strategic planning factors
2.Identify corporate planning objects 
3.Develop enterprise model
 Identify Strategic Planning Factors

     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

Identify Corporate Planning Objects


          Organizational units – departments
          Organizational locations
          Business functions – groups of business processes
          Entity types – the things we are trying to model for the database
          Information systems – application programs

Develop Enterprise Model

    Functional decomposition
     Enterprise Data Model
    Planning matrixes 
Two Approaches to Database and IS Development
  •      SDLC
  •      PROTOTYPING  

Packaged Data Models

Model components that can be purchased, customized, and assembled into full-scale data models 
Advantages
Reduced development time
Higher model quality and reliability
Two types:
Universal data models
Industry-specific data models

CASE

Computer-Aided Software Engineering (CASE) – software tools providing automated support for systems development
Three database features:
Data modeling – entity-relationship diagrams
Code generation – SQL code for table creation
Repositories – knowledge base of enterprise information