Chapter 4 - Data Modeling and the Entity-Relationship Model Flashcards
What is Data?
Recorded facts and numbers
What is the Definition of Information?
Knowledge derived from Data
Data presented in a meaningful context
Data processed by summing, ordering, averaging, comparing, or other similar operations
What is a System?
A system is defined as a set of components that interact to achieve some purpose or goal
An Information System aims to produce information and has Five (5) Components. What are those Components?
- Hardware
- Software
- Data
- Procedures
- People
What is a Business Process?
A business process is a set of activities that transform input into outputs.
Inputs»_space;Activities»_space;Outputs
What is Systems Analysis and Design?
It is the process of creating and maintaining information systems.
What is a Systems Development Life Cycle (SDLC)?
It is an approach in systems analysis and design to develop an Information System.
What are the Five (5) Steps to SDLC?
- Systems Definition
- Requirements Analysis
- Component Design
- Implementation
- System Maintenance
What is the SDLC Process in Use? (1-4)
Step (output from the current step; input for the next step)
Business Process (Start; System Needed)
System Definition (Project plan)
Requirement Analysis (Approved User Requirements)
Component Design (System Design)
What is the SDLC Process in Use? (5-7 or 8)
Step (output from the current step; input for the next step)
Implementation (System)
Users (Problem or Need for Change)
System Maintenance (Back to the Top)
System Definition…
What does the System Definition Step include?
Define the IS project goals and scope
Assess the feasibility of the project
Form the project team
Plan the project
What does the Requirements Analysis Step include?
Conduct user interviews
Evaluate existing systems
Determine needed new forms/reports/queries
Identify needed new applications features and functions
Consider security and five components of an IS
What does the Component Design Step include?
Determine hardware specifications
Determine program specifications
Create the database design
Design business procedures
Create job descriptions for business personnel
What does the Implementation Step include?
Build System components
Conduct component tests
Integrate the components
Conduct integrated component tests
Convert to the new system
What does the System Maintenance Step include?
Update the system with patches, service packs, and new software releases
Record and prioritize requests for system changes of enhancements
What are the Three (3) Steps to the Database Development Process?
- Requirements Analysis
- Component Design
- Implementation
What are the Eight (1-4) Sources of Requirements for Database Applications?
- User Interviews
- Forms
- Reports
- Queries
What are the Eight (5-8) Sources of Requirements for Database Applications?
- Application programs
- Websites
- Use Cases
- Business rules
What must be done when Creating a Database?
Data requirements must first be documented in a data model
What is the Most Popular technique used to Create Data Models?
The Entity-Relationship model which was created by Peter Chen in 1976 (now interpreted as the extended entity-relationship model)
What are the Most Important Elements of the Entity-Relationship Model? (1-4)
Entities
Attributes
Identifiers
Relationships
What are Entities?
An entity is something that users want to track.
Entities of a certain type are grouped into an entity class
An entity instance of an entity class is the occurrence of a particular entity, such as CUSTOMER 12345
What are Attributes?
They describe the entity’s characteristics
Attributes have a data type
What are Identifiers?
Attributes that name or identify entity instances. Identifiers can be unique (key) or nonunique
