Read, write, and execute are represented by the numbers 4, 2, and 1, respectively, and you add them together to get the permission

Maybe I’m the weird one here but this seems like a counter intuitive way to remeber/explain it. Each octal digit in the three digit number is actually just 3 binary digits ( 3 bit flags) in order of rwx. For example read and execute would be 101 -> 5.

At the (SQL) database level, if you are using null in any sane way, it means “this value exists but is unknown”.

Null at the SQL means that the value isn’t there, idk where you’re getting that from. SQL doesn’t have anything like JS’s undefined, there’s no other way to represent a missing value in sql other than null (you could technically decide on certain values for certain types, like an empty string, but that’s not something SQL defines).

They’re probably being downvoted for making a huge leap just from wearing pointy highheels lol. They turned a trivial reason into a non-trivial characterization/flaw about a person.