What is a ROLLBACK statement and when do you use it?

Short answer: The ROLLBACK statement is used to undo all changes made during a transaction. If an error occurs or something goes wrong, ROLLBACK ensures that the database is restored to its state before the transaction began. When to use: If any part of the transaction fails or if you wish to cancel the changes made during the transaction.

Example code

BEGIN TRANSACTION; UPDATE employees SET salary = 5000 WHERE id = 1; - Something goes wrong ROLLBACK;

Real-world example (ShopNest)

ShopNest’s SQL Server database stores customers, products, and orders. Good indexes and clear foreign keys keep checkout queries fast and safe.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.