ArcSDE permissions aren't that granular, and database extensions that permit row/column level
security are not supported by Esri (if you can make it work, congrats, but Tech Support can't help
you if it doesn't work). You'd need to pay careful attention to the extra tables created by ArcSDE
for versioning, archiving, etc, since you couldn't use ArcGIS to grant the permissions. Adding
relationship classes, domains, etc into the equation increases the level of difficulty by an order of
magnitude. I certainly wouldn't want to attempt this, and I've been working with ArcSDE since
version 1.3 and SQL-Server since 6.0.
Using multiple tables and views to join them is a less fearsome approach, but it's unlikely you'll
find someone to donate days/weeks of time to give you detailed instructions on how to proceed.
The best you can hope for is someone having published a paper on how they did something
similar, then using that as a roadmap.
- V