• The distinction doesn't make a lot of sense to me either.

    My impression is that a DBA would be skilled in installation, backup/restore, security configuration and other Administrative functions, but not necessary how to build a database from scratch.

    An Architect would seem to be someone who could design data schemas and a Developer would create stored procedures, triggers etc.

    But from what I've seen, performance tuning seems to be a DBA function, but effective performance tuning would require a lot of knowledge on how queries work and development skills.

    So a representation on what Database Administrators, Architects, Developers and Engineers do would seem to require a Venn Diagram with lots of overlap.