BSCS : Database Management Systems 2

Question 1

Which normal form eliminates transitive dependencies?

Accepted Answer

3NF

Answer

Third Normal Form (3NF) removes transitive dependencies, where a non-key attribute depends on another non-key attribute.

Question 2

In a B+ tree index, where are all data records (or pointers to them) stored?

Accepted Answer

Leaf nodes only

Answer

B+ trees store all data pointers exclusively in leaf nodes, with internal nodes holding only routing keys.

Question 3

Which SQL clause is used to filter groups after a GROUP BY?

Accepted Answer

HAVING

Answer

HAVING filters rows after aggregation by GROUP BY, whereas WHERE filters rows before grouping.

Question 4

What does the 'D' in ACID stand for?

Accepted Answer

Durability

Answer

Durability guarantees that once a transaction commits, its changes persist even if the system crashes.

Question 5

A relation is in BCNF if for every non-trivial functional dependency X → Y, X is a:

Accepted Answer

Candidate key

Answer

BCNF requires that every determinant in any non-trivial FD must be a candidate (super) key of the relation.

BSCS - Bachelor of Science in Computer Science Practice Test