Database Management System MCQs with Answers
Practice important Database Management System MCQs with answers and explanations.
Chapter: 17
Q261:
The Join operation in relational algebra is essentially a special form of which operation?
A. Cross Product
B. Union
C. Intersection
D. Set Difference
Correct Answer:
A
Chapter: 17
Q262:
If two relations have the same number of attributes and the same domains, what operation can be performed?
A. Set Difference
B. Cartesian Product
C. Intersection
D. Union
Correct Answer:
D
Chapter: 17
Q263:
What is the symbol used for the Cartesian Product operation in relational algebra?
A. ∪
B. ×
C. ∩
D. σ
Correct Answer:
B
Chapter: 17
Q264:
In the Select operation, which symbol is used to represent the predicate?
A. π
B. σ
C. ∪
D. ∩
Correct Answer:
B
Chapter: 17
Q265:
What will be the result of applying the Project operator to a relation?
A. A vertical subset of the table
B. A horizontal subset of the table
C. A new table with all attributes preserved
D. A cross product of two relations
Correct Answer:
A
Chapter: 17
Q266:
In the given example, what attributes are selected by the Project operation on the FACULTY table?
A. FacId and Salary
B. facName and Dept
C. FacId, Salary, and Rank
D. FacId and Rank
Correct Answer:
A
Chapter: 17
Q267:
Which operation is used to find the tuples that appear in one relation but not in another?
A. Set Difference
B. Union
C. Intersection
D. Cartesian Product
Correct Answer:
A
Chapter: 17
Q268:
If two relations have different domains, what operation cannot be performed on them?
A. Union
B. Intersection
C. Set Difference
D. Cartesian Product
Correct Answer:
D
Chapter: 17
Q269:
Which operator requires that both relations have the same degree and domains?
A. Union
B. Cartesian Product
C. Intersection
D. Set Difference
Correct Answer:
A
Chapter: 17
Q270:
What will be the result of the Cartesian Product of two relations R and S with m attributes and C rows in R, and n attributes and D rows in S?
A. A relation with m + n columns and C * D rows
B. A relation with m + n columns and C + D rows
C. A relation with m * n columns and C + D rows
D. A relation with m * n columns and C * D rows
Correct Answer:
A
Chapter: 17
Q271:
The Select operation in relational algebra is:
A. Commutative and Associative
B. Commutative only
C. Associative only
D. Neither commutative nor associative
Correct Answer:
B
Chapter: 17
Q272:
The Cartesian Product operation in relational algebra is:
A. Associative and Commutative
B. Commutative only
C. Associative only
D. Neither associative nor commutative
Correct Answer:
A
Chapter: 17
Q273:
What does the Join operation require between the two tables involved?
A. A relationship between the primary key and foreign key
B. A match in attribute names
C. A match in attribute domains
D. Equality of all tuples in both tables
Correct Answer:
A
Chapter: 17
Q274:
In the Project operation, what happens to duplicate rows?
A. They are eliminated
B. They are preserved
C. They are merged
D. They are counted
Correct Answer:
A
Chapter: 17
Q275:
What is the result of applying the Union operation on two relations with different degrees?
A. The operation cannot be performed
B. The degrees of the relations are adjusted
C. The result contains the degree of the larger relation
D. The result contains the degree of the smaller relation
Correct Answer:
A
Chapter: 17
Q276:
The result of the Intersection operation includes:
A. Tuples found in both relations
B. Tuples found in either relation
C. Tuples in the first relation but not in the second
D. Tuples in the second relation but not in the first
Correct Answer:
A
Chapter: 17
Q277:
Which relational algebra operator would you use to combine two relations and remove duplicates?
A. Union
B. Cartesian Product
C. Intersection
D. Set Difference
Correct Answer:
A
Chapter: 17
Q278:
The Select operation does what with the rows of a table?
A. Filters rows based on a condition
B. Combines rows from different tables
C. Eliminates duplicates from a table
D. Displays all attributes of a table
Correct Answer:
A
Chapter: 17
Q279:
The result of the Project operation will always include:
A. Specified attributes only
B. All attributes of the original relation
C. All rows of the original relation
D. Specified rows only
Correct Answer:
A
Chapter: 18
Q280:
Which type of join applies a condition before performing a cross product?
A. Equi Join
B. Theta Join
C. Natural Join
D. Semi Join
Correct Answer:
B