题解 | 不使用 join,仅使用单表查询
查找所有已经分配部门的员工的last_name和first_name以及dept_no
http://www.nowcoder.com/practice/6d35b1cd593545ab985a68cd86f28671
SELECT
(SELECT last_name from employees WHERE emp_no = d.emp_no) last_name,
(SELECT first_name from employees WHERE emp_no = d.emp_no) first_name,
dept_no
FROM dept_emp d
(SELECT last_name from employees WHERE emp_no = d.emp_no) last_name,
(SELECT first_name from employees WHERE emp_no = d.emp_no) first_name,
dept_no
FROM dept_emp d