Data persistance in Web Services?

Question

What are the solutions for data persistance in a .NET webservice?

I have a webservice. I give an id to my webservice and this one return the correct objet.

Answer 1

Alternatively, you can make your service a singleton

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single,
                 ConcurrencyMode = ConcurrencyMode.Single)]
class Service
...

However, this approach leads to huge problems in future. Do not store anything in-memory. If you do, you embed a state into the application. This leads to tremendous amount of work needed to achieve high reliability and scalability. No state, no pain.