select address.phone from (select a.phone as phone, a.address_id as address_id from (select c.address_id as address_id from rental as r join customer as c on r.customer_id = c.customer_id and r.staff_id = 1) as first join address as a on first.address_id = a.address_id and a.city_id > 500) as second join address on second.address_id = address.address_id;
select a.phone from (select c.address_id as address_id from rental as r join customer as c on r.customer_id = c.customer_id and r.staff_id = 1) as first join address as a on first.address_id = a.address_id and a.city_id > 500;
select film.title from film where film.rating = 'PG-13';
select film.title from (select i.film_id as fid from inventory as i join rental as r on i.inventory_id = r.inventory_id) as first join film on first.fid = film.film_id and film.rating = 'PG-13';
select film.film_id from film join film_category on film.rating = 'PG-13' and film_category.category_id = 1;
select film_category.film_id from (select film.film_id as fid from (select i.film_id as fid from inventory as i join rental as r on i.inventory_id = r.inventory_id) as first join film on first.fid = film.film_id and film.rating = 'PG-13') as second join film_category on second.fid = film_category.film_id and film_category.category_id = 1;
