Már átírtam. Viszont így egyáltalán nem kapom meg azt a sort, ha be van fejezve.
SELECT `employees`.*, `titles`.`title`, `salaries`.`salary`, `departments`.`dept_no`
FROM `employees`
LEFT JOIN `titles` ON (`titles`.`emp_no` = `employees`.`emp_no`)
LEFT JOIN `salaries` ON (`salaries`.`emp_no` = `employees`.`emp_no`)
LEFT JOIN `dept_emp` ON (`dept_emp`.`emp_no` = `employees`.`emp_no`)
LEFT JOIN `departments` AS `departments` ON `dept_emp`.`dept_no` = `departments`.`dept_no`
WHERE
(`titles`.`from_date` = (SELECT MAX(`from_date`) FROM `titles` WHERE `titles`.`emp_no` = `employees`.`emp_no`)) AND
(`titles`.`to_date` = '9999-01-01') AND
(`salaries`.`from_date` = (SELECT MAX(`from_date`) FROM `salaries` WHERE `salaries`.`emp_no` = `employees`.`emp_no`)) AND
(`salaries`.`to_date` = '9999-01-01') AND
(`dept_emp`.`from_date` = (SELECT MAX(`from_date`) FROM `dept_emp` WHERE `dept_emp`.`emp_no` = `employees`.`emp_no`)) AND
(`dept_emp`.`to_date` = '9999-01-01')
LIMIT 0, 20