CREATE TABLE Salaries (
    employeeNumber INT PRIMARY KEY,
    validFrom DATE NOT NULL,
    amount DEC(12 , 2 ) NOT NULL DEFAULT 0
);


INSERT INTO salaries(employeeNumber,validFrom,amount)
VALUES
    (1002,'2000-01-01',50000),
    (1056,'2000-01-01',60000),
    (1076,'2000-01-01',70000);


CREATE TABLE SalaryArchives (
    id INT PRIMARY KEY AUTO_INCREMENT,
    employeeNumber INT,
    validFrom DATE NOT NULL,
    amount DEC(12 , 2 ) NOT NULL DEFAULT 0,
    deletedAt TIMESTAMP DEFAULT NOW()
);

DELIMITER $$
CREATE TRIGGER before_salaries_delete
BEFORE DELETE
ON salaries FOR EACH ROW
BEGIN
    INSERT INTO SalaryArchives(employeeNumber,validFrom,amount)
    VALUES(OLD.employeeNumber,OLD.validFrom,OLD.amount);
END$$    

DELIMITER ;



DELETE FROM salaries WHERE employeeNumber = 1002;