Deposit Money

CREATE PROCEDURE usp_deposit_money(account_id INT, money_amount DECIMAL(19, 4))
BEGIN
    DECLARE from_account INT;

    SET from_account := (
        SELECT count(*)
        FROM accounts
        WHERE accounts.id = account_id
    );

    START TRANSACTION;

    IF (money_amount < 0 OR from_account = 0) THEN
        ROLLBACK;
    ELSE
        UPDATE accounts
        SET balance = balance + money_amount
        WHERE accounts.id = account_id;
    END IF;
END;