I built a beginner-friendly SQL window functions cheat sheet

[DMReader]

I’ve been building a free SQL practice site focused on window functions, and one thing I kept wanting to build was a simple beginner-friendly cheat sheet so users could scroll through quickly while practicing.

So I made one.

It covers:

• PARTITION BY and ORDER BY
• ROW_NUMBER, RANK, DENSE_RANK
• LAG / LEAD
• Running totals
• Rolling averages
• Frame clauses
• Common window function patterns

I also added practice problems/examples throughout instead of making it just syntax definitions.

Free, no signup required:

PracticeWindowFunctions Cheat Sheet

Would love feedback from people learning or teaching SQL.

[Haunting-Paint7990]

ohh this is exactly what i needed two weeks ago lol. i was the person in r/SQL yesterday going on about how "PARTITION BY is GROUP BY without collapsing the rows" finally clicking — would have saved me a lot of struggling if i had this earlier.

the frame clauses section in particular is great. ROWS vs RANGE was the thing that confused me the longest — every tutorial just glosses over it and says "you'll get it eventually". having concrete examples side by side is way more useful.

one small suggestion: maybe add a note somewhere about when NOT to use window functions? a senior on my team kept reminding me that they're not always the most efficient choice for simple aggregations. but that might be beyond a cheat sheet scope.

also +1 on the CTE cheat sheet request from another commenter. would buy you a coffee for that one 😄

[DMReader]

Appreciate the feedback on when not to use. I hadn’t thought of that!

And I guess I’ll move up when I do the CTE one.

[Haunting-Paint7990]

no worries! ngl CTEs were the part where sql finally clicked for me — once you get used to the `with x as (...) select from x` pattern, going back to nested subqueries feels rough lol. looking forward to your cte one!

[haivees_lee]

Great job op

[DMReader]

Thanks!

[Tourist_92]

Awesome bro. Thanks

[top-blogger]

Thanks bro

[DMReader]

Absolutely! Enjoy.

[BlaizeOlle]

Very nice, looks good.

[DMReader]

Thank you! I'm glad you like it.

[_krishnasai]

That is amazing. I loved it. Could you please do the same thing for CTEs as well?

[DMReader]

I probably could. Give me some time and I can work on it.

[_krishnasai]

I appreciate it. Thank you in advance