desc employees;
desc departments;
SELECT employee_id,department_id,location_id
from employees,departments,
locations
select e.employee_id,d.departmen_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,city
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 join departments d
on e.department_id=d.department_id;