From 14342a4bdfc863bd308df8299ad5a8c0973296d3 Mon Sep 17 00:00:00 2001
From: Anne Leschallier de Lisle <anne.leschallier@gmail.com>
Date: Sat, 7 Mar 2026 18:53:55 +0100
Subject: [PATCH 1/2] Solved lab

---
 sql_joins_myfile.sql | 42 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)
 create mode 100644 sql_joins_myfile.sql

diff --git a/sql_joins_myfile.sql b/sql_joins_myfile.sql
new file mode 100644
index 0000000..1bc1c5b
--- /dev/null
+++ b/sql_joins_myfile.sql
@@ -0,0 +1,42 @@
+-- 1. List the number of films per category.
+
+SELECT c.category_id as cat, COUNT(c.film_id) as number_of_films FROM sakila.film AS f
+JOIN sakila.film_category AS c
+ON c.film_id = f.film_id
+GROUP BY cat;
+
+
+-- 2. Retrieve the store ID, city, and country for each store.
+
+SELECT 
+s.store_id as store, 
+c.city_id as city, 
+co.country_id as country 
+FROM sakila.store AS s
+JOIN sakila.address as a
+ON s.address_id = a.address_id
+JOIN sakila.city AS c
+ON a.city_id = c.city_id
+JOIN sakila.country AS co
+ON c.country_id = co.country_id;
+
+
+
+-- 3. Calculate the total revenue generated by each store in dollars.
+
+SELECT 
+store_id as store, sum(p.amount) as total_revenue
+FROM payment as p
+JOIN customer as cust
+ON p.customer_id = cust.customer_id
+GROUP BY store_id;
+
+
+
+-- 4. Determine the average running time of films for each category.
+
+
+SELECT c.category_id as cat, avg(f.length) as running_time FROM sakila.film AS f
+JOIN sakila.film_category AS c
+ON c.film_id = f.film_id
+GROUP BY cat;
\ No newline at end of file

From bdff01d935f23e18906a26c2028530bee35cbd8f Mon Sep 17 00:00:00 2001
From: Anne Leschallier de Lisle <anne.leschallier@gmail.com>
Date: Sat, 7 Mar 2026 18:59:46 +0100
Subject: [PATCH 2/2] Solved lab

---
 sql_joins_myfile.sql | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/sql_joins_myfile.sql b/sql_joins_myfile.sql
index 1bc1c5b..2825056 100644
--- a/sql_joins_myfile.sql
+++ b/sql_joins_myfile.sql
@@ -24,19 +24,19 @@ ON c.country_id = co.country_id;
 
 -- 3. Calculate the total revenue generated by each store in dollars.
 
-SELECT 
-store_id as store, sum(p.amount) as total_revenue
-FROM payment as p
-JOIN customer as cust
-ON p.customer_id = cust.customer_id
-GROUP BY store_id;
+SELECT store.store_id, SUM(payment.amount) AS total_revenue
+FROM store
+JOIN staff ON store.store_id = staff.store_id
+JOIN payment ON staff.staff_id = payment.staff_id
+GROUP BY store.store_id;
 
 
 
 -- 4. Determine the average running time of films for each category.
 
 
-SELECT c.category_id as cat, avg(f.length) as running_time FROM sakila.film AS f
-JOIN sakila.film_category AS c
-ON c.film_id = f.film_id
-GROUP BY cat;
\ No newline at end of file
+SELECT category.name, ROUND(AVG(film.length), 2) AS average_running_time
+FROM category
+JOIN film_category ON category.category_id = film_category.category_id
+JOIN film ON film_category.film_id = film.film_id
+GROUP BY category.name;
\ No newline at end of file