How do you start a transaction in SQL?

SQLJunior~1 min read

In SQL, a transaction starts with:

sql

BEGIN TRANSACTION;

or simply

sql

START TRANSACTION;

After that, you run the queries you need, e.g. INSERT, UPDATE, DELETE. Once everything succeeds, you need to commit the changes:

sql

COMMIT;

If an error occurs or you need to cancel, you roll back:

sql

ROLLBACK;

sql

START TRANSACTION;

UPDATE accounts SET balance = balance - 100 WHERE id = 1;
UPDATE accounts SET balance = balance + 100 WHERE id = 2;

COMMIT;

If something goes wrong, you can replace COMMIT with ROLLBACK, and the database returns to its original state.

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