Database Systems Quiz

What is the purpose of three-level database architecture?

• To enhance data security by limiting access to all levels.
• To eliminate the need for data redundancy in databases.
• To simplify the user interface for database management.
• To provide data abstraction and independence, allowing changes at one level without affecting others.

What are the contents of external, conceptual, and internal levels?

• External level: user views; Conceptual level: logical structure; Internal level: physical storage.
• External level: database management; Conceptual level: data analysis; Internal level: user access.
• External level: data encryption; Conceptual level: user interface; Internal level: data processing.
• External level: physical storage; Conceptual level: user views; Internal level: logical structure.

What is the purpose of external/conceptual and conceptual/internal mappings?

• To enhance the visual design of a database application.
• To reduce the amount of data stored in a system.
• The purpose of external/conceptual and conceptual/internal mappings is to ensure accurate data representation and facilitate implementation in a database or system.
• To simplify the user interface of a database.

What does logical data independence mean?

• The ability to change the conceptual schema without affecting external schemas or applications.
• The ability to access data without any schema restrictions.
• The ability to modify data without changing the database structure.
• The ability to change external schemas without affecting the conceptual schema.

What is the distinction between DDL and DML?

• DDL is used for data retrieval; DML defines database structure.
• DDL and DML are both used for data analysis.
• DDL is a programming language; DML is a database management tool.
• DDL defines database structure; DML manipulates data within that structure.

What is a classification of data models?

• Flat file
• Hierarchical, network, relational, object-oriented, document
• CSV
• XML

What is the purpose of conceptual modeling?

• To analyze the performance of a system in real-time.
• To implement the system directly in code.
• To create detailed technical specifications for a system.
• The purpose of conceptual modeling is to provide an abstract representation of a system to facilitate understanding and communication.

What are the typical functions and services a DBMS should provide?

• User interface design tools
• Data encryption and decryption only
• Network management services
• Typical functions and services of a DBMS include data storage, retrieval, manipulation, security, integrity, transaction management, backup and recovery, and user access control.

What are the software components of a DBMS?

• Operating System
• Network Protocol
• Data Warehouse
• The software components of a DBMS include Database Engine, Database Schema, Query Processor, Transaction Management, Storage Manager, and User Interface.

What does client–server architecture mean and what are its advantages for a DBMS?

• Increased data redundancy
• Limited access to data
• Decreased performance under load
• Advantages of client-server architecture for a DBMS include improved scalability, centralized data management, enhanced security, and better resource utilization.