Really excellent concise SQL guide, and great teaching by example. At most universities in the US this content gets taught over an entire semester (and probably

Really excellent concise SQL guide, and great teaching by example. At most universities in the US this content gets taught over an entire semester (and probably shouldn't be). This guide is complete enough for 99% of industry SWE jobs outside of database optimization. It's a great service when someone takes the time to document knowledge on a single page with quality examples, and trust the reader to follow along. Reminds me of the Rudin analysis book.