Q#1: The relational model was proposed by:
(A) Peter Chen
(B) E. F. Codd
(C) Charles Babbage
(D) Alan Turing
Answer: (B) E. F. Codd
Q#2: In the relational model, data is stored in the form of:
(A) Trees
(B) Graphs
(C) Tables
(D) Files
Answer: (C) Tables
Q#3: A table in the relational model is also known as a:
(A) Tuple
(B) Relation
(C) Attribute
(D) Domain
Answer: (B) Relation
Q#4: A row in a relation is called a:
(A) Attribute
(B) Tuple
(C) Field
(D) Domain
Answer: (B) Tuple
Q#5: A column in a relation is called an:
(A) Record
(B) Tuple
(C) Attribute
(D) Key
Answer: (C) Attribute
Q#6: A domain refers to:
(A) Table name
(B) Set of permissible values
(C) Number of rows
(D) Primary key
Answer: (B) Set of permissible values
Q#7: The degree of a relation is the number of:
(A) Rows
(B) Columns
(C) Keys
(D) Tables
Answer: (B) Columns
Q#8: The cardinality of a relation is the number of:
(A) Columns
(B) Attributes
(C) Rows
(D) Domains
Answer: (C) Rows
Q#9: A primary key must be:
(A) Duplicate
(B) Null
(C) Unique
(D) Optional
Answer: (C) Unique
Q#10: A foreign key is used to:
(A) Uniquely identify records
(B) Link two relations
(C) Store duplicate values
(D) Define domain
Answer: (B) Link two relations
Q#11: A candidate key is:
(A) A non-unique key
(B) A possible primary key
(C) Always a foreign key
(D) A composite key only
Answer: (B) A possible primary key
Q#12: A super key is:
(A) A minimal key
(B) A set of attributes that uniquely identifies a tuple
(C) A foreign key
(D) A domain
Answer: (B) A set of attributes that uniquely identifies a tuple
Q#13: Which of the following is a constraint in relational model?
(A) Entity Integrity
(B) Network Integrity
(C) Hardware Integrity
(D) File Integrity
Answer: (A) Entity Integrity
Q#14: Entity integrity rule states that:
(A) Foreign key cannot be null
(B) Primary key cannot be null
(C) All attributes must be unique
(D) All values must be same
Answer: (B) Primary key cannot be null
Q#15: Referential integrity ensures that:
(A) Primary key is unique
(B) Foreign key value must match a primary key value
(C) Table must have at least one key
(D) All attributes are simple
Answer: (B) Foreign key value must match a primary key value
Q#16: A composite key is:
(A) Single attribute key
(B) Key formed by multiple attributes
(C) Foreign key
(D) Derived key
Answer: (B) Key formed by multiple attributes
Q#17: Which relational operation selects certain rows?
(A) Projection
(B) Selection
(C) Join
(D) Union
Answer: (B) Selection
Q#18: Which relational operation selects certain columns?
(A) Projection
(B) Selection
(C) Join
(D) Difference
Answer: (A) Projection
Q#19: Join operation combines:
(A) Columns of one table
(B) Rows of one table
(C) Two relations based on common attribute
(D) Domains
Answer: (C) Two relations based on common attribute
Q#20: Union operation requires relations to be:
(A) Of different degree
(B) Union compatible
(C) Without keys
(D) Of different domains
Answer: (B) Union compatible
Q#21: Intersection operation returns:
(A) All tuples
(B) Common tuples of two relations
(C) Unique columns
(D) All attributes
Answer: (B) Common tuples of two relations
Q#22: Difference operation returns:
(A) Common tuples
(B) All tuples
(C) Tuples in one relation but not in another
(D) All columns
Answer: (C) Tuples in one relation but not in another
Q#23: Which normal form eliminates partial dependency?
(A) 1NF
(B) 2NF
(C) 3NF
(D) BCNF
Answer: (B) 2NF
Q#24: Which normal form eliminates transitive dependency?
(A) 1NF
(B) 2NF
(C) 3NF
(D) 4NF
Answer: (C) 3NF
Q#25: A relation must have:
(A) Duplicate rows
(B) Unique tuples
(C) Null primary key
(D) Multiple primary keys
Answer: (B) Unique tuples
Q#26: The relational model is based on:
(A) Graph theory
(B) Set theory
(C) Tree structure
(D) File system
Answer: (B) Set theory
Q#27: In relational model, order of rows is:
(A) Important
(B) Fixed
(C) Not important
(D) Sorted automatically
Answer: (C) Not important
Q#28: In relational model, attribute values are:
(A) Atomic
(B) Composite
(C) Multivalued
(D) Repeated
Answer: (A) Atomic
Q#29: Which key uniquely identifies each tuple?
(A) Foreign key
(B) Composite key
(C) Primary key
(D) Super key
Answer: (C) Primary key
Q#30: The main advantage of relational model is:
(A) Complex structure
(B) Simplicity and flexibility
(C) High redundancy
(D) No constraints
Answer: (B) Simplicity and flexibility