Database Development Quiz DBD171/181

Database Concepts

• Databases are integral to daily activities like banking, airline ticket reservations, university management, sales, online retail, manufacturing, and human resources.
• A database consists of logically related data stored to meet organizational information requirements.

Basic Definitions

• Data: Raw facts; processed to become meaningful information.
• Database: Collection of related data managed to fulfill information needs.
• Database Management System (DBMS): Software that creates, processes, manages, and retrieves data efficiently.

Traditional Filing Systems

• Manual filing systems involve physical files and records, leading to various limitations in data management.
• Applications in traditional file systems require separate data handling, resulting in redundancy and inconsistency.

Disadvantages of Traditional File Systems

• Data redundancy and inconsistency occur from multiple applications managing their data files independently.
• Limited data integration complicates data retrieval across different files.
• Program and data dependence requires modifications when data structures change.
• Poor data sharing and control create security challenges and restricted access.

Advantages of Database Systems

• Controlled Redundancy: Reduces data duplication.
• Data Consistency: Maintains accurate and reliable information.
• Data Independence: Changes in data structure do not affect application programs.
• Data Sharing: Centralized control allows authorized users access.
• Improved Security: Protects data from unauthorized access.
• Efficient Data Management: Streamlines data handling and retrieval.

Components of a DBMS

• Data Definition Language (DDL): Defines database structure and constraints.
• Data Manipulation Language (DML): Enables insertion, updating, and query operations on data.
• Controlled Access: Manages database security, user access, and system recovery.

Role and Benefits of a DBMS

• Acts as an interface between applications and the database, managing user interactions.
• Promotes efficient data access and integrity alongside security measures.

Data Models

• Data models define database structures through concepts like entities, relationships, and constraints.
• Relational Model: Predominantly used, structured as tables (relations) consisting of rows and columns.

Example of a Relation

• An employees database might consist of a table with attributes like Employee ID, First Name, Last Name, and Gender.

Levels of Data Abstraction

• Abstracts details of data storage into user views, conceptual schemas, and physical schemas.
• Views present user-friendly interfaces, while conceptual schemas define logical structures like Entity-Relationship Diagrams (ERD).

Assessment Structure

• Evaluations include assignments, projects, class tests, and a final exam, contributing to a weighted total score across different areas: assignments (30%), projects (10%), and summative tests (40%).

Recommended Literature

• Various authoritative texts are suggested for further study, including works on relational database design and Microsoft Access.

Learning Objectives

• Establish a solid understanding of database concepts, the transition from file processing systems, and insights into data management strategies and structures.

Test your knowledge on database concepts including design, normalization, and entity relationship modeling in the Database Development DBD171/181 course. This quiz will also cover practical aspects like creating databases and tables in Access, as well as entering data and establishing relationships.