I was working on an old old old "ERP" system written in D3 PICK. It's a database, programming language and OS all in one with roots in tracking military helicopter parts in the 1960's. I was working on it in the mid-2000s. It had SQL like syntax for manipulating data, but it was interactive. So you would SELECT the rows from the table that you wanted, then those rows would be part of your state. You would then do UPD…
> if your SELECT matched no rows, the state would be empty > UPDATE and DELETE are perfectly valid actions even without a state Some may call this a fun quirk :) but I'd call it a horrible mistake in the design of the system! It should have been conceptually obvious to the designer that an empty set of rows is a perfectly valid state and is fundamentally different from "no state".
It was obviously designed by someone who had not taken any courses in formal languages, compilers and algorithms.
It had a fun quirk, the final result would change depending on which names you used for your variables.
When the phd student guiding our lab session told me to not use underscores in my variable names, I thought i'd humor her just to show her it was a stupid suggestion. But she knew more than me.