lab solved sql join hm

lab-sql-joins-solved.sql

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+USE sakila;
+
+SELECT c.name AS category, COUNT(*) AS number_of_films
+FROM film_category fc
+INNER JOIN category c ON fc.category_id = c.category_id
+GROUP BY c.name
+ORDER BY number_of_films DESC;
+
+SELECT s.store_id, ci.city, co.country
+FROM store s
+INNER JOIN address a ON s.address_id = a.address_id
+INNER JOIN city ci ON a.city_id = ci.city_id
+INNER JOIN country co ON ci.country_id = co.country_id;
+
+SELECT s.store_id, SUM(p.amount) AS total_revenue
+FROM store s
+INNER JOIN staff st ON s.store_id = st.store_id
+INNER JOIN payment p ON st.staff_id = p.staff_id
+GROUP BY s.store_id;
+
+SELECT c.name AS category, ROUND(AVG(f.length), 2) AS avg_running_time
+FROM film f
+INNER JOIN film_category fc ON f.film_id = fc.film_id
+INNER JOIN category c ON fc.category_id = c.category_id
+GROUP BY c.name
+ORDER BY avg_running_time DESC;
+
+
+SELECT c.name AS category, ROUND(AVG(f.length), 2) AS avg_running_time
+FROM film f
+INNER JOIN film_category fc ON f.film_id = fc.film_id
+INNER JOIN category c ON fc.category_id = c.category_id
+GROUP BY c.name
+ORDER BY avg_running_time DESC
+LIMIT 1;
+
+SELECT f.title, COUNT(r.rental_id) AS rental_count
+FROM film f
+INNER JOIN inventory i ON f.film_id = i.film_id
+INNER JOIN rental r ON i.inventory_id = r.inventory_id
+GROUP BY f.title
+ORDER BY rental_count DESC
+LIMIT 10;
+
+SELECT f.title, i.store_id, COUNT(i.inventory_id) AS copies_available
+FROM film f
+INNER JOIN inventory i ON f.film_id = i.film_id
+WHERE f.title = 'ACADEMY DINOSAUR'
+AND i.store_id = 1
+GROUP BY f.title, i.store_id;
+
+SELECT f.title,
+    CASE
+        WHEN IFNULL(i.inventory_id, 0) = 0 THEN 'NOT available'
+        ELSE 'Available'
+    END AS availability
+FROM film f
+LEFT JOIN inventory i ON f.film_id = i.film_id
+GROUP BY f.title, availability
+ORDER BY f.title ASC;