Question

investigate the ROLLBACK and SAVEPOINT statements and comment on how they relate to the already introduced COMMIT statement

Answer 1

The ROLLBACK statements restores the database to last committed state. It is also used with SAVEPOINT statements to jump to a savepoint in an ongoing transaction. If we have used the UPDATE command to make some changes into the database, and realize that those changes were not required, then we can use the ROLLBACK command to rollback those changes, if they were not committed using the COMMIT command.

SAVEPOINT statement is used to temporarily save a transaction so that you can rollback to that point whenever required.

In Short, we can rollback all update transactions to the last commit state or any savepoint declared. We can declare various savepoints to temporarily save the update transactions after the last commit which can be either committed or rollback later.