SQL_queries_Farnaz Zarian.txt

/*Query 1- */

SELECT f.title film_title, c.name AS category_name, COUNT(r.rental_date) rental_count
   FROM film f
   JOIN inventory i
     ON i.film_id = f.film_id
   JOIN rental r
     ON i.inventory_id = r.inventory_id
   JOIN film_category f_cat
     ON f.film_id = f_cat.film_id
   JOIN category c
     ON f_cat.category_id = c.category_id
 WHERE c.name IN ('Animation', 'Children', 'Classics', 'Comedy', 'Family')	
 GROUP BY 1,2
 ORDER BY 3 DESC;

/*Query 2- */

WITH t1 AS ( 
           SELECT f.film_id film_id_1, 
                  f.title film_title, 
                  c.NAME category_name,
		          f.rental_duration,
		   NTILE(4) OVER (ORDER BY rental_duration) AS rental_duration_quartile 
           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 
           WHERE c.NAME IN ('Animation',
							'Children',
							'Classics',
							'Comedy',
							'Family',
							'Music')), 
	 t2 AS (
           SELECT DISTINCT(i.film_id) film_id_2,
		   Count(r.rental_id) OVER (partition BY i.film_id) rental_count 
           FROM inventory i
           INNER JOIN rental r 
           ON i.inventory_id = r.inventory_id 
           ORDER BY 1) 

SELECT		t1.film_title,
    		t1.category_name,
    		t1.rental_duration,
    		t1.rental_duration_quartile,
    		t2.rental_count
FROM		t1
INNER JOIN	t2
ON		t1.film_id_1 = t2.film_id_2
ORDER BY	t1.rental_duration_quartile,
    		t2.rental_count DESC;



/*Query 3- */


WITH quartiles AS (SELECT film_title, category, rental_duration,
		NTILE(4) OVER (ORDER BY rental_duration) AS rental_duration_category
     FROM
		 (SELECT f.title film_title, c.name AS category, f.rental_duration rental_duration,
		  NTILE(4) OVER (PARTITION BY c.name ORDER BY rental_duration)
		   FROM film f
		   JOIN film_category f_cat
			 ON f.film_id = f_cat.film_id
		   JOIN category c
			 ON f_cat.category_id = c.category_id
		  WHERE c.name IN ('Animation', 'Children', 'Classics', 'Comedy', 'Family')
		 ORDER BY 2) t1)
		 
SELECT category, rental_duration_category, COUNT(*)
FROM quartiles
GROUP BY 1,2
ORDER BY 2,3 DESC;

/*Query 4- */

SELECT DATE_PART('month', CAST(r.rental_date AS DATE)) rental_month,
	   DATE_PART('year', CAST(r.rental_date AS DATE)) rental_year,
	   s.store_id,
	   COUNT(r.rental_date) count_rentals
FROM rental r
JOIN staff s 
ON r.staff_id = s.staff_id
JOIN store 
ON s.store_id = store.store_id
GROUP BY 1, 2, 3


/*Query 5- */

WITH top_paying AS (SELECT c.customer_id, SUM(p.amount) total_payment
				   FROM customer c
				   JOIN payment p
				   ON c.customer_id = p.customer_id
				   GROUP  BY 1
				   ORDER BY 2 DESC
				   LIMIT 10)

SELECT DATE_TRUNC('month', p.payment_date) pay_month,
		first_name || ' ' || last_name AS full_name,
		COUNT(p.amount) AS pay_countpermon,
		SUM(p.amount) AS pay_amt
FROM top_paying 
JOIN customer c 
ON top_paying.customer_id = c.customer_id
JOIN payment p
ON c.customer_id = p.customer_id
WHERE payment_date < '2008-01-01' AND payment_date >= '2007-01-01'
GROUP BY 1,2
ORDER BY 2,1;

/*Query 6- */

WITH top_paying AS (
			SELECT c.customer_id, SUM(p.amount) total_payment
		    FROM customer c
			JOIN payment p
			ON c.customer_id = p.customer_id
			GROUP  BY 1
			ORDER BY 2 DESC
			LIMIT 10),
			
     table2 AS (
	        SELECT DATE_TRUNC('month', p.payment_date) pay_month,
			first_name || ' ' || last_name AS full_name,
			SUM(p.amount) AS pay_amt
			FROM top_paying 
			JOIN customer c 
			ON top_paying.customer_id = c.customer_id
			JOIN payment p
			ON c.customer_id = p.customer_id
			WHERE payment_date < '2008-01-01' AND payment_date >= '2007-01-01'
			GROUP BY 1,2)
			
SELECT *, LAG(pay_amt) OVER (PARTITION BY full_name ORDER BY pay_amt) AS lag,
(pay_amt - COALESCE(LAG(pay_amt) OVER (PARTITION BY full_name ORDER BY pay_amt), 0)) AS diff
FROM table2
WHERE full_name IN ('Tommy Collazo','Rhonda Kennedy', 'Mike Way', 'Marion Snyder', 
					'Marcia Dean', 'Karl Seal', 'Eleanor Hunt','Curtis Irby', 'Clara Shaw', 'Ana Bradley')
ORDER BY diff DESC;