Introduction to Database and Transactions Flashcards
Organized collection of logically related data
Database
Stored representations of meaningful objects and events
Data
Two Classifications of Data
- Structured
2. Unstructured
Classification of data that are numbers, text, dates
Structured
Classification of data that are images, video, documents
Unstructured
Data processed to increase knowledge in the person using the data
Information
Data that describes the properties and context of user data
Metadata
Turn data into useful information that managers can use for decision making and interpretation
Graphical Displays
What are the 5 Disadvantages of File Processing?
- Program-Data Dependence
- Duplication of Data
- Limited Data Sharing
- Lengthy Development Times
- Excessive Program Maintenance
All programs maintain metadata for each file they use
Program-Data Dependence
Different systems/programs have separate copies of the same data
Duplication of Data
No centralized control of data
Limited Data Sharing
Programmers must design their own file formats
Lengthy Development Times
80% of information systems budget
Excessive Program Maintenance
- Waste of space to have duplicate data
- Causes more maintenance headaches
Problems with Data Redundancy
What is the iggest problem of Problems with Data Redundancy?
- Data changes in one file could cause inconsistencies
- Compromises in data integrity
What is the solution for Problems with Data Redundancy?
Database Approach
- Central repository of shared data
- Data is managed by a controlling agent
- Stored in a standardized, convenient form
Database Approach
What is required in Database Approach?
Database Management System (DBMS)
A software system that is used to create, maintain, and provide controlled access to user databases
Database Management System
Contains employee,
order, inventory,
pricing, and
customer data
Central Database
What are the 10 Advantages of the Database Approach?
- Program-data Independence
- Planned Data Redundancy
- Improved Data Consistency
- Improved Data Sharing
- Increased Application Development Productivity
- Enforcement of Standards
- Improved Data Quality
- Improved Data Accessibility and Responsiveness
- Reduced Program Maintenance
- Improved Decision Support
What are the 5 Costs and Risks of the Database Approach?
- New, specialized personnel
- Installation and Management Cost and Complexity
- Conversion Costs
- Need for Explicit Backup and Recovery
- Organizational Conflict
What are the 4 Elements of the Database Approach?
- Data Models
- Entities
- Relationships
- Relational Databases
Graphical system capturing nature and relationship of data.
Data Models
Two Classifications of Data Models
- Enterprise Data Model
2. Project Data Model
Classification of data model that has a high-level entities and relationships for the organization.
Enterprise Data Model
Classification of data model that has more detailed view, matching data structure in database or data warehouse.
Project Data Model
- Noun form describing a person, place, object, event, or concept
- Composed of attributes
Entities