lab-sql-joins-Solved lab

lab-sql-joins.sql

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+USE sakila;
+#Write SQL queries to perform the following tasks using the Sakila database:
+#List the number of films per category.
+
+SELECT COUNT(title) AS number_of_films, name
+FROM film
+INNER JOIN film_category
+USING (film_id)
+INNER JOIN category
+USING (category_id)
+GROUP BY name
+ORDER BY number_of_films DESC;
+
+#Retrieve the store ID, city, and country for each store.
+SELECT store_id, city, country
+FROM  store
+INNER JOIN address
+USING (address_id)
+INNER JOIN city
+USING (city_id)
+INNER JOIN country
+USING (country_id);
+
+#Calculate the total revenue generated by each store in dollars.
+SELECT store_id, SUM(amount) AS total_revenue
+FROM payment
+INNER JOIN staff
+USING (staff_id) 
+INNER JOIN store
+USING (store_id)
+GROUP BY (store_id); 
+
+#Determine the average running time of films for each category.
+SELECT AVG(length) AS average_running_time, name
+FROM film
+INNER JOIN film_category
+USING (film_id)
+INNER JOIN category
+USING (category_id)
+GROUP BY name
+ORDER BY average_running_time DESC;
+
+# Provide a list of all distinct film titles, 
+# along with their availability status in the inventory. 
+# Include a column indicating whether each title is 'Available' or 'NOT available.' 
+# Note that there are 42 titles that are not in the inventory, 
+# and this information can be obtained using a CASE statement combined with IFNULL."
+SELECT DISTINCT(title), inventory_id,
+   CASE 
+        WHEN ISNULL(return_date) THEN 'Not Available'
+        ELSE 'Available'
+    END AS availability
+FROM film    
+INNER JOIN inventory
+USING (film_id)
+INNER JOIN rental
+USING (inventory_id)
+WHERE return_date IS NULL;
+
+
+SELECT title, inventory_id,
+        CASE
+             WHEN ISNULL(inventory_id) THEN 'Not Available'
+        ELSE 'Exists'
+    END AS status
+FROM film
+LEFT JOIN inventory
+USING(film_id)
+WHERE inventory_id IS NULL;