agabaj1 / SQL-Murder-Mystery

Solution for the SQL murder mystery game.

SQL-Murder-Mystery

Challenge website: The SQL Murder Mystery

A crime has taken place and the detective needs your help. The detective gave you the crime scene report, but you somehow lost it. You vaguely remember that the crime was a ​murder​ that occurred sometime on ​Jan.15, 2018​ and that it took place in ​SQL City​. Start by retrieving the corresponding crime scene report from the police department’s database.

1. Search for information about a murder on 15 January 2018:

SELECT *
FROM crime_scene_report
WHERE type = 'murder' AND date = '20180115' AND city = 'SQL City'

Result:

date	type	description	city
20180115	murder	Security footage shows that there were 2 witnesses. The first witness lives at the last house on "Northwestern Dr". The second witness, named Annabel, lives somewhere on "Franklin Ave".	SQL City

2. Seek the witnesses:

The first witness:

SELECT *
FROM person 
WHERE address_street_name = 'Northwestern Dr' 
ORDER BY address_number DESC
LIMIT 1

Result:

id	name	license_id	address_number	address_street_name	ssn
14887	Morty Schapiro	118009	4919	Northwestern Dr	111564949

The second witness:

SELECT *
FROM person
WHERE address_street_name = 'Franklin Ave' AND name LIKE '%Annabel%'

Result:

id	name	license_id	address_number	address_street_name	ssn
16371	Annabel Miller	490173	103	Franklin Ave	318771143

3. Witnesses - interview:

SELECT p.name, p.id, i.transcript
FROM interview i
JOIN person as p
  ON i.person_id = p.id
WHERE p.id = 14887 OR p.id = 16371

Result:

name	id	transcript
Morty Schapiro	14887	I heard a gunshot and then saw a man run out. He had a "Get Fit Now Gym" bag. The membership number on the bag started with "48Z". Only gold members have those bags. The man got into a car with a plate that included "H42W".
Annabel Miller	16371	I saw the murder happen, and I recognized the killer from my gym when I was working out last week on January the 9th.

4. Check Morty Schapiro interview:

SELECT p.name, p.license_id,
  d.id, d.age, d.height, d.eye_color, d.hair_color, d.gender, 
  d.plate_number, d.car_make, d.car_model
FROM drivers_license d 
JOIN person p
  ON p.license_id=d.id
WHERE d.plate_number LIKE '%H42W%'

Result:

name	license_id	id	age	height	eye_color	hair_color	gender	plate_number	car_make	car_model
Tushar Chandra	664760	664760	21	71	black	black	male	4H42WR	Nissan	Altima
Jeremy Bowers	423327	423327	30	70	brown	brown	male	0H42W2	Chevrolet	Spark LS
Maxine Whitely	183779	183779	21	65	blue	blonde	female	H42W0X	Toyota	Prius

SELECT *
FROM get_fit_now_member
WHERE id LIKE '48Z%' AND membership_status = 'gold'

Result:

id	person_id	name	membership_start_date	membership_status
48Z7A	28819	Joe Germuska	20160305	gold
48Z55	67318	Jeremy Bowers	20160101	gold

5. Check Annabel Miller interview:

SELECT m.id, m.person_id, m.membership_status,
  c.check_in_date, c.check_in_time, c.check_out_time
FROM get_fit_now_check_in c 
JOIN get_fit_now_member m
  ON m.id = c.membership_id
WHERE c.check_in_date = 20180109 AND m.membership_status = 'gold' AND m.person_id = 67318

Result:

id	person_id	membership_status	check_in_date	check_in_time	check_out_time
48Z55	67318	gold	20180109	1530	1700

6. Check solution:

INSERT INTO solution VALUES (1, 'Jeremy Bowers')
SELECT value
FROM solution

Result:

value
Congrats, you found the murderer! But wait, there's more... If you think you're up for a challenge, try querying the interview transcript of the murderer to find the real villain behind this crime. If you feel especially confident in your SQL skills, try to complete this final step with no more than 2 queries. Use this same INSERT statement with your new suspect to check your answer.

7. Murderer - interview:

SELECT *
FROM interview
WHERE person_id = 67318

Result:

person_id	transcript
67318	I was hired by a woman with a lot of money. I don't know her name but I know she's around 5'5" (65") or 5'7" (67"). She has red hair and she drives a Tesla Model S. I know that she attended the SQL Symphony Concert 3 times in December 2017.

8. Check woman:

First option:

SELECT *
FROM person p
JOIN drivers_license d
  ON p.license_id = d.id
JOIN facebook_event_checkin f
  ON f.person_id = p.id
WHERE gender = 'female' AND d.car_make = 'Tesla' AND d.car_model = 'Model S'
AND f.event_name = 'SQL Symphony Concert'

Second option:

SELECT *
FROM person
WHERE id =
  (SELECT person_id
  FROM facebook_event_checkin
  WHERE event_name = 'SQL Symphony Concert' AND date LIKE '201712%'
  GROUP BY person_id
  HAVING COUNT(DISTINCT event_name) = 3)
OR
license_id =
  (SELECT id
  FROM drivers_license
  WHERE gender = 'female' AND hair_color = 'red' AND height BETWEEN 65 AND 67
  AND car_make = 'Tesla' AND car_model = 'Model S')
OR
id =
  (SELECT ssn
  FROM income
  ORDER BY annual_income)

Result:

id	name	license_id	address_number	address_street_name	ssn
99716	Miranda Priestly	202298	1883	Golden Ave	987756388

9. Check solution:

INSERT INTO solution VALUES (1, 'Miranda Priestly')
SELECT value FROM solution

Result:

value
Congrats, you found the brains behind the murder! Everyone in SQL City hails you as the greatest SQL detective of all time. Time to break out the champagne!