I'm not MIS, more back-end web dev and this is just personal experience, but:
data object first. If your a back-end guy you want your code working in a simple form, then want to build it out.
front end can request change of database, you just want your code working as the first step before you waste a heap of time therefore you "stub out" your code (including the dataobject) then flesh it out, make the database, complete everything. It's a personal opinion, but there you go.