28. Integer and float numbers in SQL

Have you noticed something strange about the query for the purchase rate?

SELECT 100 * COUNT(CASE WHEN status = 'customer' THEN id END) / COUNT(*) AS purchase_rate FROM users WHERE signup_date BETWEEN '2018-01-01' AND '2018-01-07'

The result should look something like this (just an example number, real query result might be different):

purchase_rate
42

⚠ You’ll see a lot of examples of tables throughout the course. Please, keep in mind that the main purpose of such examples is to reflect the structure of the query results, not the actual...

“well worth the money”
Sign up and check out 36 free lessons and exercises.

Anatoli Makarevich, author of SQL Habit About SQL Habit

Hi, it’s Anatoli, the author of SQL Habit. 👋

SQL Habit is a course (or, as some of the students say, “business simulator”). It’s based on a story of a fictional startup called Bindle. You’ll play a role of their Data Analyst 📊 and solve real-life challenges from Business, Marketing, and Product Management.

SQL Habit course is made of bite-sized lessons (you’re looking at one atm) and exercises. They always have a real-life setting and detailed explanations. You can immediately apply everything you’ve learned at work. 🚀

“well worth the money”

Fluent in SQL in a month

Master Data Analysis with SQL with real life examples from Product Management, Marketing, Finance and more.
-- Type your query here, for example this one -- lists all records from users table: SELECT * FROM users
LIMIT 500
Loading chart... ⏳
Previous lesson: Calculating purchase rate. Part 2
Next exercise: Calculating purchase rate per country