[svieira]

I suspect that people don't think about it too hard and presume that they should have only one model - that is that their REST model should map directly to their DB model which should map directly to their internal domain model (the idea that there might be two-or-more-domains and not-all-of-them-are-public hasn't even yet crossed their minds).

When you realize that sometimes your REST model may be a view-model that maps to a different storage model optimized for online-transaction-processing, neither of which map to your internal domain model directly (there are adapters for that) _then_ you get somewhere ... but of course you then have to fight off the `transformToRestModel(transformToDomainModel(retrieveDbModel(theId)))` when the three models happily coincide for a time.