Mysql三个表的连接查询

select first_name,title,salary,s.to_date

from employees e 

inner join titles t on e.emp_no = t.emp_no

inner join salaries s on e.emp_no = s.emp_no

where e.emp_no = 10001


outerjoin（外连接）:left join 、right join

innerjoin （内链接）：join