查询员工的名字、上级的名字
SELECT
e.last_name AS 员工,m.last_name AS 领导
FROM
employees AS e
JOIN
employees AS m
ON
e.manager_id = m.employee_id;

查询姓名中包含字符k的员工的名字、上级的名字
SELECT
e.last_name AS 员工,m.last_name AS 领导
FROM
employees AS e
JOIN
employees AS m
ON
e.manager_id = m.employee_id
WHERE
e.last_name LIKE ‘%k%’;