Yes, a DB2 storage option for Notes existed, but it didn't do anything to solve the basic mismatch between Notes and a) performance of Notes views in databases

Yes, a DB2 storage option for Notes existed, but it didn't do anything to solve the basic mismatch between Notes and a) performance of Notes views in databases with hundreds of thousands or more documents, b) one to many relationships / transactions / RI, or c) support SQL or other non-script approach for query or update.