SQL, for the job you want
62 chapters built backwards from real Italian SQL / Database Developer adverts, with a learning engine that measures whether you can recall this material — not whether you scrolled past it.
Every page is a real file — save the folder to a USB stick and it still works.
How this works
Every idea is explained twice
A 🧒 Simple box — the version you would give a child — and a 🎓 Professional box — the version you would give an interviewer. The switch in the top bar hides one of them, which turns any chapter into a self-test: read the simple one, then produce the professional one from memory.
Progress means retrieval
A chapter is worth 25% for reading and 75% for the test score. Read all 62 chapters and answer nothing and you are capped at 25%. That is deliberate: the number on the top bar should mean something.
Recognition and recall are different skills
Multiple choice measures recognition. An interview measures recall. So there is a viva that hides the answer until you have committed to one, and a simulator that adds a clock and takes the options away.
Nothing is behind a login
An account exists only to carry your progress between a laptop
and a phone. Everything works signed out, offline, and from file://.
The chapters
Coverage: what the adverts asked for
This course was built from five real Italian SQL / Database Developer postings, not from a syllabus. Every chapter therefore declares one of two things: the line of an advert it answers, or the reason it exists although no advert mentioned it. Both lists are generated from the same manifest that builds the sidebar, so the claim below is checkable rather than asserted.
Answered directly from an advert
| Ch. | Chapter | The line it answers |
|---|
Here anyway, and why
Ten chapters no advert asked for. Each one is here because it comes up in the interview, in the take-home, or on the second Tuesday of the job.
| Ch. | Chapter | Why it is here |
|---|
What this is not
- The mastery percentage is a fact about your test scores on these questions. It is not a fact about your ability, and it is certainly not a fact about whether anyone will hire you.
- The viva and the simulator are
self-marked. That is the weakest link in this whole site and it is
mitigated, not solved: your own words stay on screen next to the model answer, and the
rule's code terms are matched literally so "you never mentioned
SKIP LOCKED" is at least a fact. It still cannot tell whether you were right. - The leaderboard is a nudge, not an audit. Your progress document lives in your browser and you can edit it. The server re-derives the four numbers it shows rather than trusting what the browser claims, which raises the effort a little and proves nothing.
- A lost recovery code is a lost account. There is no email address on file, so there is no way round it. That is a real cost of the no-personal-data decision and it is not worth pretending otherwise.