It is a bit confusing. ArcSDE is both a product that lives in an SQL database and the API/protocol to
access that data. ArcSDE registers tables in the TABLE_REGISTRY so that it can maintain metadata
about their status with respect to ArcSDE. The geodatabase is the ArcObjects code accessing database
tables via the ArcSDE API. It, too, has a registry, implemented in many (or a few, if you're running
ArcSDE 10.0 or higher) GDB_* tables (which in turn are registered with ArcSDE).
When you register a table with ArcSDE, it's still not available to participate in geodatabase behavior
(feature datasets, relationships,...). ArcSDE-registered tables *are* avaiable for use as simple
feature classes in the geodatabase. If you register a new table with the geodatabase, it will force
ArcSDE registration if that has not been yet accomplished. No ArcSDE command can register a table
with the geodatabase (ArcSDE is not geodatabase-aware).
- V
