WorksheetsDatabase Concepts Quiz
Total questions: 25
Worksheet time: 25mins
Which of the following is not a view of data?
Internal
Conceptual
External
Logical-Physical
Which model organizes data in a tree-like structure?
Relational
Hierarchical
Network
Object-oriented
Which of the following is a feature of the relational model?
Data is stored in files
Data is stored in tables
Data is stored in hierarchies
Data is stored as graphs
Which key uniquely identifies a tuple in a relation?
Foreign key
Composite key
Primary key
Candidate key
Relational Algebra is a ___.
Procedural query language
Non-procedural language
Procedural query language
Scripting language
Which SQL command is used to retrieve data?
SELECT
INSERT
UPDATE
DELETE
In an E-R diagram, an entity is represented by:
Circle
Rectangle
Diamond
Ellipse
Which is used to represent attributes in ER diagrams?
Rectangle
Ellipse
Diamond
Line
Which of the following is a type of attribute?
Single-valued
Multi-valued
Derived
All of the above
Mapping cardinality refers to:
Number of attributes
Number of entity instances related to another
Number of databases
None of the above
Which of the following is a functional dependency?
A → B
B → A
A ←→ B
A ∈ B
Which normal form removes partial dependency?
2NF
3NF
BCNF
1NF
BCNF is a stronger version of:
1NF
3NF
2NF
5NF
A table is in 1NF if:
It has no multivalued attributes
It has atomic values
It has a primary key
It has foreign keys
Which normal form deals with multivalued dependencies?
3NF
4NF
BCNF
2NF
Which of the following causes redundancy?
Functional dependency
Referential integrity
Domain constraints
None of the above
Join Dependency is addressed in:
2NF
3NF
4NF
5NF
Which of these ensures lossless decomposition?
Functional dependency
Lossless join property
Dependency preservation
Normalization
Which property ensures all dependencies are preserved?
Lossless decomposition
2NF
Dependency preservation
Projection
An attribute that can be derived from other attributes is:
Composite
Derived
Single-valued
Multi-valued
Which is a non-additive join?
Full outer join
Lossless join
Left join
Self join
A transaction is a:
Logical unit of work
Physical process
User command
Memory block
Which property ensures that changes are permanent?
Atomicity
Consistency
Durability
Isolation
Which schedule is serializable but not serial?
Non-serial
Conflict-serializable
Strict
View-equivalent
Which SQL command is used to undo a transaction?
COMMIT
ROLLBACK
SAVEPOINT
DELETE
