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SQLIntermediate#transactions

Explain the ACID properties.

Atomicity: a transaction is all-or-nothing. Consistency: it moves the database from one valid state to another. Isolation: concurrent transactions do not corrupt each other. Durability: committed data survives a crash.

Example
BEGIN;
UPDATE accounts SET balance = balance - 500 WHERE id = 1;
UPDATE accounts SET balance = balance + 500 WHERE id = 2;
COMMIT; -- both succeed or neither does

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