HardSQL challenge #358WINDOW FUNCTIONRANKINGANALYTICS

Relative Salary Rank

Assign normalized rank between 0 and 1 for salaries.

The challenge runs on the SQLabHub practice database (SQLite) and uses the employees table. You can solve it in the browser, with nothing to install.

Solve This SQL Challenge

The task

Assign normalized rank between 0 and 1 for salaries.

A correct answer returns 120 rows with 13 columns: id, first_name, last_name, email, department, department_id, title, salary, hire_date, manager_id, city, status, normalized_rank.

Tables used in this challenge

`employees` 120 rows

id INTEGER (PK) · first_name TEXT · last_name TEXT · email TEXT · department TEXT · department_id INTEGER · title TEXT · salary REAL · hire_date TEXT · manager_id INTEGER · city TEXT · status TEXT

First 3 rows of the employees table
id	first_name	last_name	email	department	department_id	title	salary	hire_date	manager_id	city	status
1	William	Lewis	wlewis18@corp.io	Customer Success	7	Senior CS Manager	61774	2022-07-24	NULL	San Diego	active
2	John	Miller	jmiller51@corp.io	Legal	8	Paralegal	191694	2021-08-09	NULL	San Diego	active
3	Daniel	Rivera	drivera50@corp.io	Engineering	1	VP Engineering	135067	2016-06-06	NULL	Houston	active

The first rows of each table are shown. See how all the tables relate on the database schema page.

Expected output

Expected output of the challenge
id	first_name	last_name	email	department	department_id	title	salary	hire_date	manager_id	city	status	normalized_rank
37	Paul	Thomas	pthomas53@corp.io	Design	10	UI Designer	46044	2017-10-01	5	San Antonio	active	0
81	Joseph	Lewis	jlewis89@corp.io	HR	4	HR Coordinator	50360	2019-03-19	8	New York	active	0.008403361344537815
54	Laura	Jones	ljones44@corp.io	Finance	5	Controller	50463	2023-10-26	3	Indianapolis	active	0.01680672268907563
4	Melissa	Smith	msmith33@corp.io	Engineering	1	VP Engineering	51465	2022-04-13	NULL	Fort Worth	active	0.025210084033613446
90	Barbara	Baker	bbaker85@corp.io	Sales	3	Sales Rep	52164	2023-01-22	5	San Francisco	active	0.03361344537815126

First 5 of 120 rows. This is the output of the model solution on the practice database. The task does not fix a sort order, so your rows may come back in a different order.

What you practise

Expressing a row's position as a fraction with PERCENT_RANK()

Hint and approach

Try the challenge first. Open these only when you need them.

Show the hint

PERCENT_RANK

Show the step-by-step approach

How the model solution is built, in the order the database evaluates it:

Read from the employees table.
Compute PERCENT_RANK(), the relative position from 0 to 1, ordered by salary.

Model solution

Checking your session…

What to watch for

PERCENT_RANK(). PERCENT_RANK() returns a value between 0 and 1, not a percentage. Multiply by 100 to display it as one.