Which SQL command would you issue to revert all uncommitted changes in the current transaction?

• A. Savepoint
• B. Rollback
• C. End Transaction
• D. Commit

Answer: (B)

Transactions group multiple statements into a single unit of work. You can either commit the whole set, making all changes permanent, or roll it back to undo everything since the transaction began.

To revert all uncommitted changes in the current transaction, you use a rollback. This undoes every statement executed in that transaction, leaving the database as it was before the transaction started.

Saving to a savepoint is for partial undo: you can roll back only to that specific point, not all changes from the start. Committing would apply the changes, not revert them. Ending the transaction isn’t the standard command for undoing changes in most databases.