Which happen in world of javascript. It has null and undefined. Null variable is a variable / property that's defined and set with null, while undefined is a variable / property that's not defined yet (or maybe not initialized, I forgot).
I hope at least SQL will give another comparison operation, such as the current equal sign (=) means a.prop is not null && b.prop is not null && a.prop equal b.prop (for not defined yet).
Let's say another sign like a.prop *= b.prop, meaning a.prop is null && b.prop is null || a.prop = b.prop (for our intention is both value are empty).
I hope at least SQL will give another comparison operation, such as the current equal sign (=) means a.prop is not null && b.prop is not null && a.prop equal b.prop (for not defined yet).
Let's say another sign like a.prop *= b.prop, meaning a.prop is null && b.prop is null || a.prop = b.prop (for our intention is both value are empty).