Quiz for ROLLBACK

Q1: Which SQL command undoes changes made in the current transaction?

A. COMMIT B. ROLLBACK C. SAVEPOINT D. RESTART

Q2: What does the ROLLBACK statement do in SQL?

A. Commits all changes B. Saves changes temporarily C. Undoes changes since last COMMIT D. Locks the table

Q3: When is ROLLBACK used?

A. After saving changes B. Before DELETE operation C. When an error occurs D. To optimize query

Q4: Which SQL command cancels a transaction?

A. ROLLBACK B. SAVEPOINT C. COMMIT D. GRANT

Q5: Which of the following is TRUE about ROLLBACK?

A. It saves changes permanently B. It creates a backup C. It reverses uncommitted changes D. It deletes the table

Q6: Can ROLLBACK undo a DELETE operation?

A. Yes, if not committed B. No C. Only on UPDATE D. Only on INSERT

Q7: What happens if ROLLBACK is executed after COMMIT?

A. Changes are undone B. No effect C. Error is thrown D. Data is duplicated

Q8: Which of these is typically paired with ROLLBACK?

A. TRUNCATE B. SAVEPOINT C. GRANT D. REVOKE

Q9: What does ROLLBACK TO SAVEPOINT do?

A. Deletes all rows B. Undoes all changes C. Reverts to a specific savepoint D. Commits the transaction

Q10: Which command is used to undo part of a transaction?

A. COMMIT B. ROLLBACK TO C. RELEASE SAVEPOINT D. START TRANSACTION

Q11: Is ROLLBACK a DML command?

A. Yes B. No C. Partially D. Only with DELETE

Q12: Which keyword is used to start a transaction explicitly?

A. BEGIN B. START TRANSACTION C. INIT D. OPEN

Q13: How does ROLLBACK affect AUTO-COMMIT mode?

A. Disables it B. Throws error C. No effect D. Prevents further queries

Q14: Which command makes changes permanent in a transaction?

A. ROLLBACK B. COMMIT C. SAVEPOINT D. LOCK

Q15: ROLLBACK reverts changes made by which type of commands?

A. DDL B. TCL C. DML D. DCL

Q16: What is the default behavior if no SAVEPOINT is set and ROLLBACK is executed?

A. Nothing happens B. Whole transaction is rolled back C. Only last query undone D. Error occurs

Q17: What is the effect of ROLLBACK on a TRUNCATE statement?

A. It reverts it B. No effect C. It causes error D. It logs the command

Q18: Can ROLLBACK be nested in SQL?

A. Yes B. No C. Only in PL/SQL D. Depends on DBMS

Q19: Which command is used after ROLLBACK to continue transaction?

A. COMMIT B. CONTINUE C. SAVEPOINT D. START TRANSACTION

Q20: Does ROLLBACK affect database schema changes?

A. Yes B. No C. Sometimes D. Only on DROP

Q21: Which scenario best requires a ROLLBACK?

A. After SELECT query B. After successful COMMIT C. On constraint violation D. During table creation