I'm currently in the process of converting an old project over to use nHibernate and I have a quick question about caching.
In the project we have what was called an 'Entity cache' which really is an Object store consisting of a hashtable of hashtables of objects. This was used to hold certain data that wouldn't change, was not likely to change, and didn't really matter if it did change. Periodically this cache would refresh itself - reloading all the data from the database.
Since this cache relied on a thin service layer to retrieve values from the dao it still works under nHibernate (since it was never tied down to a specific implementation), but I am aware that nHibernate provides some caching of its own. What my question really comes down to is whether the nHibernate caching can be set to auto-refresh entities?
Thanks in advance.

None of the NHibernate second-level caches will reload data automatically, by themselves. NHibernate will re-add to the cache any items that have expired when you query for them. This should give the same result, except for the slight delay when hitting the DB to reload the cache.

(Actually, I don't know anything about the new NCache. It might do what you want.)