You can export model component data to an ODBC (Open Database Connectivity) database. The exported data can include project parameters that have been assigned to one or more element categories in the project. For each element category, Revit exports a database table for model types and another table for model instances.
ODBC export uses metric units only. If a project uses Imperial units, Revit converts all measurements to metric units before exporting to ODBC. When you use data from the resulting database, remember that the measurements reflect metric units. Use a database function to convert the measurements back to Imperial units if necessary.
Revit can export to the same database multiple times. When exporting to an empty database, Revit creates new tables. When you export a project to a populated database, Revit updates table information to match the project. This allows you to customize the database and re-export data as the project changes.