Database Management System MCQs with Answers
Practice important Database Management System MCQs with answers and explanations.
Multiple Choice Questions
Q271: The Select operation in relational algebra is:
- A: Commutative and Associative
- B: Commutative only
- C: Associative only
- D: Neither commutative nor associative
View Answer
B
Q272: The Cartesian Product operation in relational algebra is:
- A: Associative and Commutative
- B: Commutative only
- C: Associative only
- D: Neither associative nor commutative
View Answer
A
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
View Answer
A
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
View Answer
A
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
View Answer
A
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
View Answer
A
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
View Answer
A
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
View Answer
A
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
View Answer
A
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
View Answer
B