> I'll play the devils advocate: what ever logical structure of the data you come up with will not line-up with relational DB tables
That contradicts my experience. The relational model isn't a panacea, but it lets me model most scenarios adequately. Whenever the relational model is deficient, what I want is more powerful schemas (sum and product tables, constraints spanning several tables, etc.), not less.
> Hell, we have been trying and failing to do Object-Relational Mapping for years now, and it's still a shit-show.
I'm inclined to think the problem is actually at the object-oriented end of the bridge: https://news.ycombinator.com/item?id=11861520
> With NoSQL I'll just dump the new document structure and call it a day (or rather, deal with the differences in the application layer).
Correctly managing these differences without help from schema-aware tools is rather painful.
I'll play the devils advocate: what ever logical structure of the data you come up with will not line-up with relational DB tables - I have had the pleasure of designing relational schemas for cyclic graphs. Hell, we have been trying and failing to do Object-Relational Mapping for years now, and it's still a shit-show. I could name a long list of ORM libraries and an even longer list of their various deficiencies.
Say you've thought rigorously about the logical structure of your data and v1 is out, and now a change comes along and you need an extra field or 5. Renormalize your structure, write some migration scripts (in both directions, just in case you want to downgrade). With NoSQL I'll just dump the new document structure and call it a day (or rather, deal wiht the differences in the application layer).