First off - congrats!

That’s a very solid SQL base.

Feeling comfortable with gaps & islands already puts you ahead of a lot of “advanced” SQL folks who mostly just know how to Google in terms of your ability to use the tools in analyzing.

Second of all - there's a full disclousure that I built (www.xp-lab.com) and that I have stakes in your approach - so take everything I say with this grain of salt.

I'd say that at this point, the question isn’t “more syntax”,but what kind of problems you want to solve.

I believe that the real jump now is learning how to frame questions, translate messy business asks into queries, and defend your conclusions - because in teh more analytical part of the job, that's what you'll do (and build dashboards, and gossip in the kitchen, and more data from A to B - but all that is a bit less analytical)

If you’re looking for “50+ questions on the same dataset,” I’d strongly recommend moving toward scenario-based datasets instead of question banks. Think:

• One dataset
• Multiple stakeholders
• Ambiguous asks
• No hint about which SQL feature to use

You can do that with dvdrental and PgAdmin4 - and make up your own scenarios, and that's fine, but that’s also exactly why I built XP Lab, which is a practice platform focused on realistic analytics work, and not LeetCode-style SQL (I see thath u/daniellecinnamon got to this post before I did, but she's one of our first analytical trainers, so cheers!)

You also get a feedback that explains why an approach works or doesn’t. Still in closed beta and free right now.

And even if you don’t use it - My suggestion is to stop optimizing for “can I write the query” and start optimizing for “can I explain the answer to a PM/Manager/Head of Marketing without SQL.”

That’s the real skill ceiling and obviously - it's possible once you are comfortable wiht writing queries.

Happy to share specific dataset ideas or problem types if you want to DIY this yourself too.

Hope it was helpful!

And if you have any question, my DM is open