IBPS SO IT Officer DBMS Quiz 2026, FREE PDF & Quiz

1. A database model represents records as nodes connected by multiple links, allowing one child record to have multiple parents. Which model is this?

2. A bank wants a report containing every customer, including customers who have never placed an order. Customers is the left table and Orders is the right table. Which join is most appropriate?

3. Which SQL clause filters individual rows before grouping?

4. Which SQL clause is used to filter groups produced by GROUP BY?

5. Which aggregate function counts only non-NULL values of a specified column?

6. A relation is in 2NF when it is in 1NF and every non-prime attribute is fully dependent on what?

7. Which normal form is primarily concerned with eliminating transitive dependency of non-key attributes on a key?

8. In BCNF, for every non-trivial functional dependency X −> Y, what must be true?

9. Which ACID property ensures that a committed transaction’s effects survive a system crash?

10. Which ACID property means a transaction executes completely or has no effect at all?

11. Two concurrent transactions read and update the same item, causing one update to overwrite the other. This anomaly is called:

12. Under strict two-phase locking, when are exclusive locks released?

13. Which index structure is especially suitable for range queries because leaf nodes are linked in sorted order?

14. A hash index is generally most effective for which type of predicate?

15. Which key uniquely identifies a row in a relation and is chosen from the candidate keys?

16. A foreign key in table A references a primary/candidate key in table B. Which integrity rule does this support?

17. Which relational algebra operation returns selected rows satisfying a condition?

18. Which relational algebra operation chooses specific columns from a relation?

19. A correlated subquery is distinguished because it:

20. Which SQL command removes all rows from a table while keeping the table definition, and is typically a DDL operation in many DBMSs?