Guides
Practical guides on AI tools, software development and SQL. Independent educational content.
Guide list
- SQL
The JOIN that multiplies the sum
Why the total goes up after joining orders with items, how to see it happen and three ways to fix it.
- Claude Code
Court of 12 Claudes
How to install and use the /court skill in Claude Code to put your idea on trial before you spend time on it.
- Claude Code
Double Esc does not undo everything
How to use Claude Code’s rewind to restore an earlier state of your code and conversation, what it cannot undo, and the habit that protects your project.