Who are all the employees working in the city of London?
select * from employees as t1 join departments as t2 on t1.department_id = t2.department_id join locations as t3 on t2.location_id = t3.location_id where t3.city = 'London'
What are their full names and salaries?
select first_name, last_name, salary from employees as t1 join departments as t2 on t1.department_id = t2.department_id join locations as t3 on t2.location_id = t3.location_id where t3.city = 'London'