CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Losing useful information when an unrelated row is deleted is a:
A. Deletion anomaly
B. Insertion anomaly
C. Primary-key benefit
D. Query optimization
Correct Answer: A
A deletion anomaly occurs when deleting one record unintentionally removes another important fact.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Being unable to add a fact without adding unrelated data is an:
A. Insertion anomaly
B. Deletion anomaly
C. Sorting error
D. Join result
Correct Answer: A
An insertion anomaly occurs when table design prevents adding one fact independently.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Changing the same fact in many rows can cause an:
A. Update anomaly
B. Index advantage
C. Backup benefit
D. Security role
Correct Answer: A
An update anomaly occurs when duplicated facts must be changed in multiple places and may become inconsistent.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
The intentional addition of redundancy for performance is called:
A. Denormalization
B. Normalization
C. Encryption
D. Validation
Correct Answer: A
Denormalization deliberately combines or duplicates data to reduce joins and improve read performance.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Boyce-Codd Normal Form requires every determinant to be a:
A. Candidate key
B. Foreign key only
C. Calculated field
D. Report heading
Correct Answer: A
BCNF requires every determinant in a functional dependency to be a candidate key.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
A transitive dependency occurs when a non-key attribute depends on:
A. Another non-key attribute
B. Only the primary key directly
C. A backup device
D. The database password
Correct Answer: A
A transitive dependency exists when one non-key attribute determines another non-key attribute.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Third Normal Form removes:
A. Transitive dependencies
B. All candidate keys
C. Every relationship
D. All numeric values
Correct Answer: A
Third Normal Form requires 2NF and removes transitive dependencies among non-key attributes.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
A partial dependency occurs when a non-key attribute depends on:
A. Only part of a composite key
B. The entire candidate key
C. No attribute
D. A report title
Correct Answer: A
Partial dependency means a non-key field depends on only one part of a composite key.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Second Normal Form removes:
A. Partial dependencies
B. All primary keys
C. All foreign keys
D. Every text value
Correct Answer: A
Second Normal Form requires 1NF and removes partial dependency on part of a composite key.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
Which of the following violates First Normal Form?
A. Storing several phone numbers in one field
B. Using a primary key
C. Storing one date in one field
D. Creating a foreign key
Correct Answer: A
Multiple values in one field are not atomic and therefore violate First Normal Form.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
A table is in First Normal Form when:
A. Each field contains atomic values
B. Every table has no rows
C. All values are encrypted
D. Every column contains multiple lists
Correct Answer: A
First Normal Form requires each cell to contain one atomic value and removes repeating groups.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
The process of organizing database tables to reduce redundancy is called:
A. Normalization
B. Encryption
C. Compilation
D. Pagination
Correct Answer: A
Normalization organizes data into well-structured tables to reduce duplication and anomalies.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
What is the main purpose of an Entity-Relationship Diagram?
A. To visually model entities, attributes, and relationships
B. To repair hardware
C. To create passwords
D. To print only one table
Correct Answer: A
An ERD helps design and communicate the logical structure of a database.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
In Crow's Foot notation, the crow's-foot symbol represents:
A. Many
B. One
C. Zero only
D. A primary key
Correct Answer: A
The three-pronged crow's-foot symbol indicates the 'many' side of a relationship.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
In many ER diagrams, a primary key attribute is shown by:
A. Underlining the attribute name
B. Deleting the attribute
C. Writing it in lowercase only
D. Adding a page number
Correct Answer: A
A common ERD convention is to underline attributes that form the primary key.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
An entity that cannot be uniquely identified without another entity is called a:
A. Weak entity
B. Strong entity
C. Independent entity
D. Database view
Correct Answer: A
A weak entity depends on a related strong entity for identification.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
An attribute calculated from other attributes is called a:
A. Derived attribute
B. Composite key
C. Primary attribute
D. Foreign key
Correct Answer: A
A derived attribute is calculated, such as Age derived from DateOfBirth.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
An attribute that may contain several values for one entity is called:
A. Multivalued attribute
B. Primary attribute
C. Foreign attribute
D. Atomic attribute
Correct Answer: A
A multivalued attribute can hold more than one value, such as multiple phone numbers.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
An attribute that can be divided into smaller meaningful parts is called:
A. Composite attribute
B. Derived attribute
C. Single-valued attribute
D. Foreign attribute
Correct Answer: A
A composite attribute can be broken down, such as Address into Street, City, and PostalCode.
CSS - PMS - CCE - PCS - Basic Computing
Database Basics
An association between two or more entities is called a:
A. Relationship
B. Data type
C. Constraint
D. Report
Correct Answer: A
A relationship represents how entities are connected to each other.