> For every "unknown" value, the sgbd will NOT decide for you if it's true or false But it did decide. It could either return the row, or not return the row -

> For every "unknown" value, the sgbd will NOT decide for you if it's true or false But it did decide. It could either return the row, or not return the row - there's no middle ground. By not returning the row, it implied that null is not not 'crazy'. If it actually wanted not to decide, it could return an error.