I use vim bindings for shell, so doing dangerous things I usually open it in edit mode and have to physically do :wq to execute. Much less chance of being destructive, and you can easily drop the output into clipboard or a file from here.

Otherwise, simply having a mindset of, I'm doing dangerous things also goes a long way.

Never do things if you are in a panicked/frantic state.

Edit: I guess running galera is actually a blessing. I can't run any write/update methods on our qa/prod data...