[打卡]张士晨 多表查询

select employee_id,department_name,locations                           
from employees,departments
WHERE employees.department_id=departments.department_id;

SELECT e.employee,d.department_name
from employees e,departments d
where e.department_id=d.department_id(+);

SELECT employee_id,department_name
from employees  e JOIN departments d
on e.department_id=d.department_id;



SELECT employee_id,department_name
from employees  e  inner JOIN departments d
on e.department_id=d.department_id;


SELECT employee_id,department_name
from employees  e JOIN departments d
on e.department_id=d.department_id
JOIN locations l
on d.location_id=l.location_id;

SELECT employee_id,department_name
from employees e left outer join departments d
on e.department_id=d.department_id;

SELECT employee_id,department_name
from employees e left  join departments d
on e.department_id=d.department_id;


SELECT employee_id,department_name
from employees e RIGHT join departments d
on e.department_id=d.department_id;