Lab solved

sakila2.sql

@@ -0,0 +1,97 @@
+use sakila;
+
+-- 1. You need to use SQL built-in functions to gain insights relating to the duration of movies:
+-- 1.1 Determine the **shortest and longest movie durations** and name the values as `max_duration` and `min_duration`.
+SELECT 
+    MAX(length) AS max_duration,
+    MIN(length) AS min_duration
+FROM film;
+
+-- 1.2. Express the **average movie duration in hours and minutes**. Don't use decimals.
+SELECT 
+    FLOOR(AVG(length) / 60) AS hours,
+    ROUND(AVG(length) % 60) AS minutes
+FROM film;
+
+-- 2.1 Calculate the **number of days that the company has been operating**.
+SELECT 
+    DATEDIFF(MAX(rental_date), MIN(rental_date)) AS days_operating
+FROM rental;
+
+-- 2.2 Retrieve rental information and add two additional columns to show the **month and weekday of the rental**. Return 20 rows of results.
+SELECT 
+    *,
+    MONTHNAME(rental_date) AS rental_month,
+    DAYNAME(rental_date) AS rental_weekday
+FROM rental
+LIMIT 20;
+
+-- 2.3 *Bonus: Retrieve rental information and add an additional column called `DAY_TYPE` with values **'weekend' or 'workday'**, depending on the day of the week.*
+SELECT 
+    *,
+    CASE
+        WHEN DAYOFWEEK(rental_date) IN (1, 7) THEN 'weekend'
+        ELSE 'workday'
+    END AS day_type
+FROM rental;
+
+-- 3. You need to ensure that customers can easily access information about the movie collection. To achieve this, retrieve the **film titles and their rental duration**. If any rental duration value is **NULL, replace** it with the string **'Not Available'**. Sort the results of the film title in ascending order.
+SELECT 
+    title,
+    IFNULL(length, 'Not Available') AS rental_duration
+FROM film
+ORDER BY title ASC;
+
+-- 4. *Bonus: The marketing team for the movie rental company now needs to create a personalized email campaign for customers. To achieve this, you need to retrieve the **concatenated first and last names of customers**, along with the **first 3 characters of their email** address, so that you can address them by their first name and use their email address to send personalized recommendations. The results should be ordered by last name in ascending order to make it easier to use the data.*
+SELECT 
+    CONCAT(first_name, ' ', last_name) AS full_name,
+    SUBSTRING(email, 1, 3) AS email_prefix
+FROM customer
+ORDER BY last_name ASC;
+
+-- Challenge 2 -
+-- 1. Next, you need to analyze the films in the collection to gain some more insights. Using the `film` table, determine:
+-- 1.1 The **total number of films** that have been released.
+SELECT COUNT(*) AS total_films 
+FROM film;
+
+-- 1.2 The **number of films for each rating**.
+ SELECT 
+    rating,
+    COUNT(*) AS num_films
+FROM film
+GROUP BY rating;
+
+--  1.3 The **number of films for each rating, sorting** the results in descending order of the number of films.
+SELECT 
+    rating,
+    COUNT(*) AS num_films
+FROM film
+GROUP BY rating
+ORDER BY num_films DESC;
+
+-- 2. Using the `film` table, determine:
+-- 2.1 The **mean film duration for each rating**, and sort the results in descending order of the mean duration. Round off the average lengths to two decimal places. This will help identify popular movie lengths for each category.
+SELECT 
+    rating,
+    ROUND(AVG(length), 2) AS mean_duration
+FROM film
+GROUP BY rating
+ORDER BY mean_duration DESC;
+
+-- 2.2 Identify **which ratings have a mean duration of over two hours** in order to help select films for customers who prefer longer movies.
+SELECT 
+    rating,
+    ROUND(AVG(length), 2) AS mean_duration
+FROM film
+GROUP BY rating
+HAVING ROUND(AVG(length), 2) > 120
+ORDER BY mean_duration DESC;
+
+-- 3. *Bonus: determine which last names are not repeated in the table `actor`.*
+SELECT 
+    last_name
+FROM actor
+GROUP BY last_name
+HAVING COUNT(*) = 1
+ORDER BY last_name ASC;