? MySQL START TRANSACTION

? Quick Overview

START TRANSACTION is used in MySQL to begin a database transaction. A transaction allows you to execute multiple SQL statements as a single logical unit, ensuring data consistency and control over commit or rollback.

? Key Concepts

Transaction groups multiple SQL statements together
Changes are temporary until committed
Rollback can undo changes if something goes wrong
Works only with transactional storage engines like InnoDB

? Syntax / Theory

A transaction starts with START TRANSACTION and ends with either COMMIT or ROLLBACK.

? View Code Example

-- Start a new transaction
START TRANSACTION;

-- Insert a new record
INSERT INTO accounts (name, balance) VALUES ('Rahul', 5000);

-- Update another record
UPDATE accounts SET balance = balance - 1000 WHERE name = 'Amit';

-- Save all changes permanently
COMMIT;

? Live Output / Explanation

All SQL statements execute successfully and the changes are permanently stored in the database after COMMIT. If any statement fails before commit, you can use ROLLBACK to undo all changes.

? Tips & Best Practices

Always use transactions for financial or critical operations
Keep transactions short to avoid locking issues
Use ROLLBACK during testing to avoid permanent changes
Ensure tables use InnoDB engine

? Try It Yourself

Start a transaction and insert multiple rows, then rollback
Update records inside a transaction and commit them
Test behavior with and without commit