Questions And Answers
Q1. What is the primary purpose of a database management system
(DBMS)?
A) Replace all application software
B) Provide organized storage, retrieval, modification, and control of data
C) Convert all unstructured data into images
D) Eliminate the need for data security
Correct Answer: B) Provide organized storage, retrieval, modification, and
control of data
Rationale: A DBMS manages stored data and provides mechanisms for
querying, updating, security, integrity, concurrency, and administration.
Q2. Which example represents structured data?
A) A collection of audio recordings
B) Free-form customer comments
C) Customer records stored in defined rows and columns
D) A folder containing photographs
Correct Answer: C) Customer records stored in defined rows and columns
Rationale: Structured data follows a predefined organization, such as fields
and records in relational database tables.
Q3. Which example is most clearly unstructured data?
A) A table of employee IDs and salaries
B) A spreadsheet containing inventory quantities
C) A relational table of customer addresses
D) A collection of videos, images, and free-form documents
Correct Answer: D) A collection of videos, images, and free-form documents
Rationale: Unstructured data does not naturally conform to a fixed tabular
schema.
Q4. What is metadata?
A) A duplicate copy of every database row
B) Data that describes other data, such as column names, types, and
constraints
, C) Data deleted from a table
D) A type of database password
Correct Answer: B) Data that describes other data, such as column names,
types, and constraints
Rationale: Metadata describes the structure, meaning, properties, and
organization of stored data.
Q5. What does a database schema describe?
A) Only the current values stored in rows
B) The operating-system version
C) The defined structure of database objects and their relationships
D) The physical location of every user
Correct Answer: C) The defined structure of database objects and their
relationships
Rationale: A schema defines objects such as tables, attributes, keys,
constraints, and relationships rather than individual data values.
Q6. What is data redundancy?
A) Encrypting sensitive data twice
B) Removing all repeated values from a database
C) Creating backup media
D) Unnecessary duplication of the same information in multiple locations
Correct Answer: D) Unnecessary duplication of the same information in
multiple locations
Rationale: Excessive redundancy wastes storage and can create
inconsistent copies of the same fact.
Q7. Which problem can result when duplicate copies of the same
customer address are stored in several places?
A) Every query becomes mathematically invalid.
B) The primary key disappears automatically.
C) Storage becomes unlimited.
D) One copy may be changed while another remains outdated.
Correct Answer: D) One copy may be changed while another remains
outdated.