I’m not talking about “oops” mistakes.
I’m talking about things you decided to do on purpose, and then deeply regretted later.
Me personally, my biggest database regret was that time almost twenty years ago when I ran a Profiler trace from my desktop computer.
My very slow desktop computer.
Which was connected to production over a VPN.
I can’t remember what happened first – running out of space on my C drive, or my VPN disconnecting – but in the hot mess of it all, I fielded a call from my manager asking about why the production SQL Server