SQL19 查找所有员工的last_name和first_name以及对应的dept_name
SELECT last_name, first_name, dept_name
FROM employees AS e LEFT JOIN (
SELECT emp_no, dept_name
FROM dept_emp de LEFT JOIN departments d
ON de.dept_no = d.dept_no)k
ON e.emp_no = k.emp_no;
SELECT last_name, first_name, dept_name
FROM employees AS e LEFT JOIN (
SELECT emp_no, dept_name
FROM dept_emp de LEFT JOIN departments d
ON de.dept_no = d.dept_no)k
ON e.emp_no = k.emp_no;