Database Management System Quiz

What is the ACID property of transactions that ensures changes are either fully committed or completely rolled back?

• Atomicity

• Consistency

• Isolation

• Durability

What is the purpose of referential integrity constraints in a database?

• To define data validation rules

• To enforce relationships between tables

• To improve query performance

• To control user access permissions

An Information System can benefit from a well-designed database by achieving which of the following?

• Increased data redundancy

• Improved data quality and consistency

• Difficulty in data sharing

• Limited data accessibility

In a hierarchical data model, how are records related?

• Parent-child relationships

• Network of interconnected records

• Two-dimensional table structure

• No relationships exist

Which of the following best describes the function of an Entity-Relationship (ER) diagram?

• To define data types and constraints

• To visualize relationships between entities

• To store and manipulate actual data

• To control user access to the database

What is the main difference between a primary key and a unique key in a database table?

• Primary keys cannot be null, while unique keys can be.

• A table can have only one primary key, but multiple unique keys.

• Primary keys must be foreign keys in another table, while unique keys can't be.

• There is no significant difference, they serve the same purpose.

What is the primary function of a query optimizer in a DBMS?

• To define table structures

• To manage user access control

• To choose the most efficient execution plan for queries

• To perform data backup and recovery

What is the difference between SQL DDL and DML statements?

• DDL deals with data manipulation, while DML defines database structure.

• DDL defines data structure while DML deals with data manipulation.

• Both DDL and DML create new data in the database.

• They are synonymous and serve the same purpose.

In a Banking System, what type of relationship would exist between the "Customer" entity and the "Account" entity?

• One-to-one

• Many-to-many

• One-to-many

• Many-to-one

Which of the following data types is best suited for storing website URLs in a database?

• Integer

• Character (CHAR)

• Varchar

• Date