A while ago, I published Miroslav Schonauer's popular high-level overview of Revit and database integration. Here is an additional useful note from Anthony Hauck on this topic:
Question: How can I integrate Revit with an ERP solution or an SQL database?
Answer: Revit information can be exported to an ODBC-compatible database. ODBC export is a native feature of Revit. The Labs posting RDBLink demonstrates a similar capability using the API, with the additional feature of being able to change some parameters within a Revit model by editing the resulting database and re-importing the changes. Some of these parameter changes can affect Revit model geometry.
The availability of RDBLink has already been mentioned briefly previously.
