Database recap

1. What is metadata in a database?

• The actual data stored in the database
  

• Data that describes other data

• A backup of the database

• A list of queries executed in the database

2. Which of the following is NOT typically stored in a data dictionary?

• Data stored in tables

• Table structures
  

• User access permissions

• Index information

3. What is the primary purpose of an index in a database?

• To ensure referential integrity
  

• To enforce uniqueness in tables

• To store backup copies of data

• To speed up data retrieval operations

4. Which of the following statements about indexes is FALSE?

• Every table must have at least one index

• An index can be created on one or more columns

• Indexes increase storage requirements

• An index improves read performance but may slow down write operations

5. What is the role of a transaction log in a database system?

• To store raw data before processing
  

• To store metadata for tables and columns

• To maintain a history of all changes made to the database

• To track the number of users accessing the database

6. Which of the following best describes a database application?

• A collection of tables used for storing information
  

• A software system that interacts with a database to manage and manipulate data

• A system that only allows users to view data but not modify it

• A tool used only for database backups

7. In the context of databases, what is denormalization?

• The process of optimizing queries
  

• The process of reducing redundancy in a database

• The process of compressing data for storage efficiency

• The process of adding redundancy for performance improvement

What is the main advantage of using a NoSQL database like MongoDB?

• 
  Ability to handle large volumes of unstructured data

• Strong compliance

• Stores data in a tabular format

• Strong schema enforcement

Which of the following best describes a relational database?

• A database that stores data in key-value pairs
  
  

• A flexible database with no predefined schema relationships

• A database where data is stored in tables with predefined relationships

• A hierarchical data storage system

Which of the following is NOT a feature of a relational database?

• 
  
  Flexible schema

• Structured query language (SQL)

• Tables with predefined relationships