SQLens: LeetCode Helper & Study Notes

Your own LeetCode study notebook. Turn the code you write into revision notes, then export them as PDF or JSON.

SQLens turns the SQL practice and other free questions on the leet into notes you can actually revise from. Most SQL prep disappears the moment you close the tab. You solve a window-function problem, you feel good about it, and three weeks later you solve it again from scratch. SQLens fixes that by keeping a notebook of your own work. WHAT IT DOES • Save a problem you are working on with one click, or Alt+Q • Generate study notes from the query YOU wrote — intuition, approach, complexity • Automatic tagging of the SQL clauses your query uses (joins, window functions, CTEs, aggregation and more) so you can see your own patterns • Export everything as JSON, or as a printable revision PDF • Optional AI solutions, gated behind a thinking timer you set yourself — once you lock it in, it cannot be shortened, paused, or cancelled WHAT IT DOES NOT DO • Nothing is captured automatically — every save is a button press • Nothing is ever posted, submitted, or published on your behalf • Premium problems are never captured • Exports contain your own work and a link back to the problem, never the problem text itself AI FEATURES ARE OPTIONAL The notebook works without any AI. To use the writing assistant you supply your own free Groq API key, stored locally on your machine. FREE AND PRO Free covers 2 captures a week, one PDF and one JSON export a week, 2 AI write-ups a month, and 2 AI solutions in total. Pro removes the limits at $2.50/month or $12/year. SQLens is an independent study tool. It is not affiliated with, endorsed by, or sponsored by LeetCode or any other practice platform.