[wvenable]

Ah but then how do you record that the measurement actually happened but did not produce a value? I want a record of that failure.

I mean sure, you could do yet another table. But honestly that level of normalization is much more work than it's worth. Just because it's some academic definition doesn't make it right.

[recursive]

You put a record in the Measurement table, and none in the Value table.

> But honestly that level of normalization is much more work than it's worth

Yes. I question whether it's worth anything to begin with.

[rawgabbit]

     Select M.*, V.* from Measurement as M left outer join Value_table as V…

You end up with nulls again.

[recursive]

Yes. That's part of the semantics of outer joins.

But there is no stored null representing 'no value'.