Найти все увеличения зарплат сотрудников с момента найма

CREATE TABLE `employees` (
`emp_no` int(11) NOT NULL,
`birth_date` date NOT NULL,
`first_name` varchar(14) NOT NULL,
`last_name` varchar(16) NOT NULL,
`gender` char(1) NOT NULL,
`hire_date` date NOT NOT NULL,
PRIMARY KEY (`emp_no`)
);
CREATE TABLE `salaries` (
`emp_no` int(11) NOT NULL,
`salary` int(11) NOT NULL,
`from_date` date NOT NULL,
`to_date` date NOT NULL,
PRIMARY KEY (`emp_no`, `from_date`)
);

SELECT конец.emp_no, (конец.salary - начало.salary) AS growth FROM (SELECT emp_no, salary FROM salaries WHERE to_date = '9999-01-01') AS конец LEFT JOIN (SELECT s.emp_no, s.salary FROM salaries s INNER JOIN employees e ON s.emp_no = e.emp_no WHERE s.from_date = e.hire_date) AS начало ON начало.emp_no = конец.emp_no ORDER BY growth

-- Текущая зарплата
(SELECT emp_no, salary FROM salaries WHERE to_date = '9999-01-01') конец

-- Начальная зарплата
(SELECT s.emp_no, s.salary FROM salaries s INNER JOIN employees e ON s.emp_no = e.emp_no WHERE s.from_date = e.hire_date) начало