We are using Sql Server Database as backend for our product. We want to protect our database from tampering. That means the database can only be updated through the app. However if DB has been modified using backend or by any other means then app should raise alert next time used and stop working.

Can anyone help me on this regard?

Thanks,
Chanan

Well, who would be updating it in the backend? What kind of credentials do they have?

Classic vendor paranoia.

Unfortunately, you can not secure something that is on a server that someone else owns. They can always disable whatever items you put in their way. The best solution to this would be to offer your software as a service. Then you own the server, and control access with as iron a fist as you like.