[lab-sql-self-cross-join]Giacomo

lab11.sql

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+-- 1. Get all pairs of actors that worked together.
+select * 
+from sakila.film_actor a1
+inner join sakila.film_actor a2
+on a1.film_id = a2.film_id
+and a1.actor_id <> a2.actor_id
+order by a1.actor_id;
+
+-- 2. Get all pairs of customers that have rented the same film more than 3 times.
+
+create table sakila.tempo_customer 
+select customer_id, film_id from sakila.rental re
+left join sakila.inventory inv
+on re.inventory_id = inv.inventory_id
+group by 1,2;
+
+select s1.customer_id , s2.customer_id, count(s1.film_id) as count_film 
+from sakila.tempo_customer s1
+inner join sakila.tempo_customer s2
+on s1.customer_id <> s2.customer_id and s1.film_id = s2.film_id
+group by s1.customer_id , s2.customer_id
+having count_film >3 and s1.customer_id < s2.customer_id
+order by 3 desc;
+
+
+select count(customer_id) from sakila.tempo_customer;
+
+-- 3. Get all possible pairs of actors and films.
+select concat(first_name, ' ', last_name) actor_name, title from sakila.actor
+cross join sakila.film;