1. . A relational database stores data in:
(A) Tree structures only
(B) Tables consisting of rows and columns
(C) Graph structures only
(D) Files without structure
2. . In relational databases, a tuple refers to:
(A) A database schema
(B) A column in a table
(C) A foreign key
(D) A single row in a table
3. . A relation in a relational database is:
(A) A table with rows and columns
(B) A backup file
(C) A compressed table
(D) An encrypted file
4. . Primary key in a table:
(A) Encrypts data automatically
(B) Uniquely identifies each row
(C) Compresses the table
(D) Deletes old records
5. . Foreign key is used to:
(A) Compress files
(B) Encrypt data
(C) Establish a link between two tables
(D) Delete logs
6. . Candidate key refers to:
(A) Only the primary key
(B) Any attribute or set of attributes that can uniquely identify a tuple
(C) Encrypted attributes
(D) Compressed columns
7. . Super key is:
(A) A set of one or more attributes that uniquely identify a tuple
(B) A compressed key
(C) An encrypted key
(D) A backup key
8. . Alternate key is:
(A) A foreign key
(B) A candidate key not chosen as the primary key
(C) An encrypted key
(D) Compressed column
9. . Composite key is:
(A) A compressed key
(B) A backup key
(C) A foreign key
(D) A key formed from two or more attributes to uniquely identify a tuple
10. . Domain in relational databases refers to:
(A) A table name
(B) The set of valid values an attribute can have
(C) A compressed column
(D) An encrypted key
11. . Referential integrity ensures:
(A) Data is encrypted
(B) Tables are compressed
(C) Foreign key values must match primary key values in the referenced table
(D) Backups are consistent
12. . Entity integrity ensures:
(A) All tables are compressed
(B) Foreign key values are unique
(C) Primary key values cannot be NULL
(D) Data is encrypted
13. . Relational algebra is used to:
(A) Delete old records
(B) Compress tables
(C) Encrypt data
(D) Perform queries and operations on relational databases
14. . Relational calculus is:
(A) A backup procedure
(B) A table compression method
(C) A non-procedural query language based on mathematical predicate calculus
(D) Encryption algorithm
15. . A view in relational databases is:
(A) Compressed file
(B) A physical backup
(C) An encrypted table
(D) A virtual table derived from a query
16. . Normalization in relational databases is used to:
(A) Compress files
(B) Reduce redundancy and improve data integrity
(C) Encrypt data
(D) Delete old records
17. . Denormalization is done to:
(A) Compress tables
(B) Encrypt tables
(C) Improve query performance by reducing joins
(D) Delete redundant rows
18. . Tuple relational calculus is:
(A) Backup procedure
(B) A compression method
(C) An encryption algorithm
(D) A declarative language where queries describe what to retrieve, not how
19. . Attribute in a relational table refers to:
(A) A row
(B) A column representing a property of an entity
(C) A table
(D) A database schema
20. . The main purpose of relational database concepts is to:
(A) Delete old records
(B) Compress files
(C) Encrypt tables
(D) Organize data efficiently, maintain integrity, and support queries