Database Restore

A backup of a database from a server replaces a similar database when I restore it on another server. What I want is to add to the existing data and not to replace it. How can I overcome this situation? Please I sincerely need your help.

there are couple of ways to do this (a) Replication (b) Log shipping (c) Database mirroring etc. but these kind of High Availablility method need to be monitored and maintained constantly. Other ways may be designing your own mechanism with implimenting trigger. it involved lot of work.

Madhu