can database data be crypted so that even the system administrator
cannot read it ?

I want my data be hosted by an internet provider.

He (the internet provider) must have sysadm privileges as he will
take care of local backups.

However I want to be the only one who can read table data.

I access table data thru a client program (written by me) and TCP/IP.

TIA

Duilio Foschi