[couradical]

But at step 3, you've already validated the code change. You know that the name only code works as intended, and you're just cleaning up old code at that point. I do agree that there is a potential for failure at that point, but I'd think it to be reasonably mitigated in comparison to making the change and needing to then roll back.

Step 4 is non destructive from a data perspective, as those columns would be "zombie" data. they'd exist, but nothing would be referencing them at that point, and the data would simply exist in a different form.

If you're talking about representing the data differently, yes that would happen, and in a case like the above, you'd be much better off by preserving normalization and using a view to combine into a "name" entity. Th