1520094343_sql_project_AlwynPinto.sql

/* Welcome to the SQL mini project. For this project, you will use
Springboard' online SQL platform, which you can log into through the
following link:

https://sql.springboard.com/
Username: student
Password: learn_sql@springboard

The data you need is in the "country_club" database. This database
contains 3 tables:
    i) the "Bookings" table,
    ii) the "Facilities" table, and
    iii) the "Members" table.

Note that, if you need to, you can also download these tables locally.

In the mini project, you'll be asked a series of questions. You can
solve them using the platform, but for the final deliverable,
paste the code for each solution into this script, and upload it
to your GitHub.

Before starting with the questions, feel free to take your time,
exploring the data, and getting acquainted with the 3 tables. */



/* Q1: Some of the facilities charge a fee to members, but some do not.
Please list the names of the facilities that do. */
SELECT name,
		membercost
	FROM Facilities
	WHERE membercost !=0

/* Q2: How many facilities do not charge a fee to members? */
SELECT COUNT(name)
	FROM Facilities
	WHERE membercost =0

/* Q3: How can you produce a list of facilities that charge a fee to members,
where the fee is less than 20% of the facility's monthly maintenance cost?
Return the facid, facility name, member cost, and monthly maintenance of the facilities in question. */

SELECT facid,
		name,
		membercost,
		monthlymaintenance
	FROM Facilities
	WHERE membercost < monthlymaintenance



/* Q4: How can you retrieve the details of facilities with ID 1 and 5?
Write the query without using the OR operator. */
SELECT facid, name
	FROM Facilities
	WHERE facid IN ( 1, 5 ) 

/* Q5: How can you produce a list of facilities, with each labelled as
'cheap' or 'expensive', depending on if their monthly maintenance cost is
more than $100? Return the name and monthly maintenance of the facilities
in question. */
SELECT name,
	CASE WHEN monthlymaintenance > 100 THEN "expensive"
		ELSE "Cheap" END AS "Exp or Cheap"
	FROM Facilities
	ORDER BY "Exp or Cheap"

/* Q6: You'd like to get the first and last name of the last member(s)
who signed up. Do not use the LIMIT clause for your solution. */
SELECT firstname, surname, joindate
FROM `Members`
ORDER BY joindate DESC 

/* Q7: How can you produce a list of all members who have used a tennis court?
Include in your output the name of the court, and the name of the member
formatted as a single column. Ensure no duplicate data, and order by
the member name. */

SELECT 
	DISTINCT CONCAT(z.firstname,' ', z.surname) AS full_name,
	facilities.name as facility_name

FROM
	(SELECT members.memid, 
		bookings.facid, 
		members.firstname, 
		members.surname
		FROM Members AS members
		RIGHT JOIN Bookings AS bookings
		ON members.memid =bookings.memid) z
RIGHT JOIN Facilities as facilities
	ON facilities.facid = z.facid

WHERE facilities.facid=0 OR facilities.facid=1

/* Q8: How can you produce a list of bookings on the day of 2012-09-14 which
will cost the member (or guest) more than $30? Remember that guests have
different costs to members (the listed costs are per half-hour 'slot'), and
the guest user's ID is always 0. Include in your output the name of the
facility, the name of the member formatted as a single column, and the cost.
Order by descending cost, and do not use any subqueries. */

SELECT CONCAT (members.firstname," ",members.surname) AS fullname,
	SUM(bookings.slots*facilities.membercost + bookings.slots*facilities.guestcost) AS cost
	
	FROM `Bookings` AS bookings
			LEFT JOIN `Members` AS members 
			ON bookings.memid = members.memid
			LEFT JOIN Facilities as facilities
			ON bookings.facid =facilities.facid
	WHERE bookings.starttime LIKE '2012-09-14%' AND (bookings.slots*facilities.membercost + bookings.slots*facilities.guestcost) >30


GROUP BY 1
ORDER BY 2 DESC



/* Q9: This time, produce the same result as in Q8, but using a subquery. */

SELECT subquery.fullname,
		SUM(subquery.cost) as total_cost

FROM  (SELECT CONCAT (members.firstname," ",members.surname) AS fullname,
		(bookings.slots*facilities.membercost + bookings.slots*facilities.guestcost) AS cost
			FROM `Bookings` AS bookings
			LEFT JOIN `Members` AS members 
			ON bookings.memid = members.memid
			LEFT JOIN Facilities as facilities
			ON bookings.facid =facilities.facid
			WHERE bookings.starttime LIKE '2012-09-14%' AND (bookings.slots*facilities.membercost + bookings.slots*facilities.guestcost) >30) AS subquery

GROUP BY fullname
ORDER BY total_cost DESC


/* Q10: Produce a list of facilities with a total revenue less than 1000.
The output of facility name and total revenue, sorted by revenue. Remember
that there's a different cost for guests and members! */

SELECT 	facilities.name AS facility_name,
		SUM(bookings.slots*facilities.membercost + bookings.slots*facilities.guestcost) AS revenue
	
	FROM `Bookings` AS bookings
			LEFT JOIN Facilities as facilities
			ON bookings.facid =facilities.facid
	GROUP BY 1
HAVING revenue < 10000