What he means (i guess) is that he wants a full notification stack from DB to client.
DB
DB (Update/Insert Trigger)
DB (Update/Insert Trigger) :
External Hook
DB (Update/Insert Trigger) :
External Hook -> API Listeners
DB (Update/Insert Trigger) :
External Hook -> API Listeners -> Web Service (Persistent, socket not closed)
DB (Update/Insert Trigger) :
External Hook -> API Listeners -> Web Service (Persistent, socket not closed) -> Client
The bold part is database vendor specific and you'll probably only get it to work with MS SQL Server after beating your self up a few times.
See:
this