[sql-self-cross-join] Laura

[sql-self-cross-join] Laura.sql

@@ -0,0 +1,34 @@
+-- 1. Get all pairs of actors that worked together.
+select f1.film_id, f2.actor_id
+from sakila.film_actor as f1
+inner join sakila.film_actor as f2
+on f1.film_id = f2.film_id
+and f1.actor_id <> f2.actor_id
+;
+
+-- 2. Get all pairs of customers that have rented the same film more than 3 times.
+select c1.customer_id, c2.customer_id, count(distinct r1.inventory_id) as number_of_rentals
+from sakila.customer as c1
+inner join sakila.rental as r1
+on c1.customer_id = r1.customer_id
+inner join sakila.inventory as i1
+on r1.inventory_id = i1.inventory_id
+inner join sakila.film as fm
+on i1.film_id = fm.film_id
+inner join sakila.inventory as i2
+on fm.film_id = i2.film_id
+inner join sakila.rental as r2
+on i2.inventory_id = r2.inventory_id
+inner join sakila.customer as c2
+on r2.customer_id = c2.customer_id
+where c1.customer_id <> c2.customer_id
+group by 1,2
+having number_of_rentals >3
+order by 3 desc
+;
+
+-- 3. Get all possible pairs of actors and films.
+Select concat(first_name, ' ', last_name) as actor_name, title, film_id
+from sakila.actor
+cross join sakila.film
+;