SQL practice: Transactions: The Undo Button

Inside BEGIN/ROLLBACK, raise all Accessory prices by 10%, check with a SELECT, then roll back. Confirm afterwards that nothing changed.

Do the same but with COMMIT instead, then put the prices back with a second UPDATE. (Notice how much more careful you have to be.)

Inside a transaction, insert a new order and then roll it back. Confirm the order is gone.

Explain why a stock transfer between branches should be one transaction rather than two separate statements.

Inside BEGIN/ROLLBACK, delete all Cancelled orders, count what's left, then roll back.

Start a transaction with BEGIN. Insert a customer named 'Savepoint Retail' with city 'Mumbai' and customer_type 'Retail'. Create a SAVEPOINT named step_one. Then insert another customer named 'Bad Record' with city 'Goa' and customer_type 'Retail'. Roll back to step_one using ROLLBACK TO SAVEPOINT step_one, and finally COMMIT the transaction.