The ROLLBACK command is a transactional control command used to roll back the changes that are not saved to the database. You have to create a SAVEPOINT before you delete records from the table so that you can roll back to that SAVEPOINT whenever needed.
Here is an example of how you can create SAVEPOINT and how to rollback to that SAVEPOINT:
DELETE FROM Employee
WHERE E_id = 797;
ROLLBACK to savepoint_1;
You can check out this SQL Tutorial blog to know more about ROLLBACK and how to use ROLLBACK.