Oracle DB administrator-specific security features Yesterday I was presenting an internet banking solution to a potential client management. My offer is based on using MS SQL Server 2008 RDBMS. 

One of the client's officers mentioned, that Oracle's RDBMS has some "specific" features that allow a security department to ensure that no sensitive data is visible to an admin, that MS SQL doesn't have.

For me it is hard to imagine how can this be mitigated, unless preventing access to some tables in a DB.  

My question - is there really a "know-how" in Oracle RDBM when it comes to security tuning, that MS SQL does not implement?
I do not know if there is a SQL Server equivalent but they are probably talking about Oracle Database Vault. It allows administrators to take care of operations on the database without having access to the data. Now if your organization doesn't make the distinction between a role where DBAs handle operations functions vs DBAs that have access to data (to run DDL scripts, DML, etc) then this isn't much help. But it can help limit exposure in those situations where only a few people need to access data but where many help keep up with database operations.