DBMS MIDTERM EXAM MCQ (2024-25)

Which of the following best explains the primary purpose of normalization in database design?

• To speed up query execution

• To remove the need for primary keys

• To minimize redundancy and maintain integrity

What is a characteristic of a weak entity in an ER diagram?

• Has its own unique primary key

• Depends on a related strong entity for identification

• Cannot be connected to other entities

Which schema focuses purely on the actual storage of data?

• Conceptual Schema

• Physical Schema

• Logical Schema

What is a potential disadvantage of database normalization?

• Reduces data integrity

• Increases query complexity

• Leads to data redundancy

In the ACID properties of a DBMS, what does 'Atomicity' ensure?

• Transactions are always fast

• A transaction is fully completed or not executed at all

• All users have equal access

What is NOT a correct description of a multivalued attribute?

• It stores multiple values

• It is represented by double ellipses in ERD

• It can act as a unique identifier

Which of the following best defines a foreign key?

• A column that stores unique values only

• A reference to the primary key of another table

• A key used for encryption purposes

Which of the following is not part of the 1NF requirement?

• Atomicity

• No duplicate rows

• Full functional dependency

What is meant by 'partial dependency' in normalization?

• All attributes depend on the entire primary key

• A non-key attribute depends on part of a composite primary key

• There are no dependencies between attributes

In an ER Diagram, which symbol is used to represent attributes?

• Rectangle

• Diamond

• Ellipse