Comment by Szpadel

there is also other scenario, field might obviously looks like it should have value, and in check it might event always have it, but it might be "lazy" value.

eg. you might have some bug CSV uploaded and your have number of rows in it, your app could insert record without this number and async process would fill that later.

there might be even some corner case where null value is possible

I believe solution here isn't to check what fields do not use null, but to improve process of creating such migration. either you should create second ticket for next release to update db or commit new migration to some kind of next branch.