Appendix How to generate number or date sequences

273. How to generate number or date sequences

In this lesson, we’ll figure out how to generate a sequence of numbers or dates. In the course, we saw how handy it is to have such a helper table: if in some query we aggregate by date, for example, we might see a result like this:

date number_of_purchases
2020-01-01 12
2020-01-04 8
2020-01-12 9

What we really want, especially when plotting this data, is to have no missing dates in the output:

date number_of_purchases
2020-01-01 12
2020-01-02 0
2020-01-03 0
2020-01-04 8
2020-01-05 0

If we only have a table with a date...

“well worth the money”
Sign up and check out 37 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
Loading chart... ⏳
Previous lesson: NULL functions
You’ve completed the last lesson 👏 ❤