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lab_mysql_select.sql

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+USE sakila;
+-- INSTRUCTIONS
+
+-- How many distinct (different) actors last names are there?
+
+	select count(distinct last_name) from actor;
+
+-- In how many different languages where the films originally produced?
+-- (Use the column language_id from the film table)
+
+	select count(distinct (language_id)) from film;
+
+
+ -- How many movies were released with "PG-13" rating?
+
+ select rating, count(rating) as numfilms
+ from film
+ where rating = 'PG-13'
+ group by rating;
+
+
+-- Get 10 the longest movies from 2006.
+
+select * from film
+where film.release_year >= 2006
+order by film.length desc
+limit 10;
+
+-- How many days has been the company operating (check DATEDIFF() function)?
+
+SELECT DATEDIFF(max(rental_date),min(rental_date)) as period1 FROM rental;
+
+-- Show rental info with additional columns month and weekday. Get 20.
+
+select *, MONTH(rental_date) as month,dayofweek(rental_date) as week_day from rental;
+
+
+-- Add an additional column day_type with values 'weekend' and 'workday' 
+-- depending on the rental day of the week.
+
+select *, IF(dayofweek(rental_date)<= 5, "work", "weekend") as day_type from rental;
+
+-- How many rentals were in the last month of activity?
+
+select year(rental_date) as year_r, month(rental_date) as month_r,count(rental_id) 
+from rental 
+group by year(rental_date),month(rental_date)
+order by year(rental_date) desc,month(rental_date) desc
+limit 1;
+
+-- Get film ratings.
+select rating,count(rating) as numfilms from film
+group by rating
+order by numfilms desc;
+
+
+-- Get release years.
+select release_year,count(release_year) as numfilms from film
+group by release_year
+order by numfilms desc;
+
+-- Get all films with ARMAGEDDON in the title.
+select * from film where title like "%ARMAGEDDON%";
+
+-- Get all films with APOLLO in the title
+select * from film where title like "%APOLLO%";
+
+-- Get all films which title ends with APOLLO.
+select * from film where title like "%APOLLO";
+-- Get all films with word DATE in the title.
+select * from film where title like "% DATE%" or title like 'DATE%';
+-- Get 10 films with the longest title.
+select title, LENGTH(title) as l_movie from film order by l_movie desc limit 10;
+
+-- Get 10 the longest films.
+select title , length from film order by length desc limit 10;
+
+-- How many films include Behind the Scenes content?
+
+select count(*) as numfilms from film 
+where special_features like "%Behind the scenes%";
+
+-- List films ordered by release year and title in alphabetical order.
+
+select * from film order by release_year, title ASC;
+
+-- Drop column picture from staff.
+ALTER TABLE staff
+DROP COLUMN picture;
+
+-- A new person is hired to help Jon. Her name is TAMMY SANDERS, and she is a customer. 
+-- Update the database accordingly.
+INSERT INTO staff (first_name, last_name,address_id,email,store_id,active,username)
+SELECT  first_name,last_name,address_id,email,2,1,first_name
+FROM customer
+WHERE customer_id= (select customer.customer_id from customer where first_name ='TAMMY' and last_name = "SANDERS");
+
+
+-- Add rental for movie "Academy Dinosaur" by Charlotte Hunter from Mike Hillyer at Store 1. 
+-- You can use current date for the rental_date column in the rental table. 
+-- Hint: Check the columns in the table rental and see what information you would need to add there. 
+-- You can query those pieces of information. 
+-- For eg., you would notice that you need customer_id information as well. 
+-- To get that you can use the following query
+
+-- select customer_id from sakila.customer
+-- where first_name = 'CHARLOTTE' and last_name = 'HUNTER';
+-- Use similar method to get inventory_id, film_id, and staff_id.
+
+insert into rental (rental_date, inventory_id, customer_id, staff_id) values
+((current_date()),
+(select max(inventory_id) from inventory where film_id = (select max(film_id) from film where title = "Academy Dinosaur") and store_id = 1) ,
+(select customer_id from customer where first_name = 'CHARLOTTE' and last_name = 'HUNTER'),
+(select staff_id from staff where first_name = 'MIKE' and last_name = 'HILLYER')
+);
+
+-- Delete non-active users, but first, 
+-- create a backup table deleted_users to store customer_id, email, 
+-- and the date for the users that would be deleted. Follow these steps:
+
+create table deleted_users as select customer_id,email,current_date() from customer where active = 0;
+
+-- create table deleted_users (customer_id INT, email VARCHAR(20),date default current_date())
+-- insert into deleted_users (customer_id,email,date.......
+
+SET FOREIGN_KEY_CHECKS=0;
+
+delete from customer where active = 0;
+
+SET FOREIGN_KEY_CHECKS=1
+
+-- Check if there are any non-active users
+-- Create a table backup table as suggested
+-- Insert the non active users in the table backup table
+-- Delete the non active users from the table customer