> I'm not sure what you mean by "more or less work."

I would like to mesure the impact in our applications if we add such new
columns in our system. As I could understand it?s not so transparent, right?

Should not some applications be changed, if a new column is added to a
table? If the application is inserting lines without column names for
example, or using the select *.

Thanks in advance,

Reimer