We aren't necessarily stuck with SQL (for instance, right now there are LDAP or XML or RDF-oriented datastores out there with fairly open APIs and decent intero

We aren't necessarily stuck with SQL (for instance, right now there are LDAP or XML or RDF-oriented datastores out there with fairly open APIs and decent interop), but we are stuck with "articulation of the domain twice, once for a datastore, and once for application" unless one programming language finally conquers all the others and becomes the only platform your schema needs to be usable with.