Используя схему OracleHR с ее таблицами следует написать запрос на языке SQL, который позволит показать всех сотрудников которые не состоят ни в одном департаменте из таблиц Employees и Departaments.

  • SELECT first_name FROM employees WHERE department_id IS NOT NULL;
  • SELECT first_name FROM employees WHERE department_id IS NULL;
  • SELECT first_name FROM employees e LEFT ENJOIN departments d ON (e.department_id = d.department_id)
  • SELECT first_name FROM employees e LEFT JOIN departments d OFF (e.department_id = d.department_id)
  • SELECT first_name FROM employees e LEFT JOIN departments d OFF (e.department_id = d.department_id) WHERE d.department_name IS NULL;
  • SELECT first_name FROM employees e LEFT JOIN departments d ON (e.department_id = d.department_id) WHERE d.department_name IS NULL;
  • SELECT first_name FROM employees e LEFT SPLIT departments d ON (e.department_id = d.department_id)
  • SELECT first_name FROM employees e RIGHT JOIN departments d ON (e.department_id = d.department_id)
Для просмотра статистики ответов нужно войти.