Bryan Evans of the DrySQL project felt that ActiveRecord falls a bit short of complying with the DRY principle. If you have tables or columns that aren't compatible with the naming conventions, then you need to redefine some of your database artifacts in application code. As well, ActiveRecord associations and validations are redundant specifications of database constraints. Bryan wants to be able to change his database schema without needing to re-wire the ORM layer(s) of dependent applications. He wants to avoid (as much as possible) the situation where he's averse to making a change to his database schema because of the effort that would be required to sync up dependent applications.
Since ActiveRecord uses the database's information schema to dynamically retrieve column metadata, Bryan asked: "Can this strategy be applied to all database artifacts?"