second-level-cache

We have an application that uses Hibernate's 2nd level caching to avoid database hits. I was wondering if there is some easy way to invalidate the Java application's Hibernate 2nd level cache when an outside process such as a MySQL administrator directly connected to modify the database (update/insert/delete). We are using EHCache as our 2nd level cache implementation. We use a mix of @Cache(usage = CacheConcurrencyStrategy.READ_WRITE) and @Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE), and we don't have Optimistic concurrency control enabled using timestamps on each entity. The

Im working on developing a webapplication with Spring 3 and Hibernate 3.6. At the moment I try to understand how Caching with Spring and Hibernate works. I found some sources about Caching with Hibernate and some about Spring and I try to bring my informations together now. I still got some questions to both frameworks and Id be glad if someone could answer them or tell me if the facts listed here are correct. Most of the time, short answers (yes/no) would be sufficient. I think that this list can be useful for others too, who want to understand how caching with spring and hibernate works.

I have trouble understanding when hibernate hits the second level cache and when does it invalidate the cache. This is what I currently understand: Second level cache stores entities between sessions, scope is the SessionFactory You have to tell which entities to cache, no entity will get cached by default Query cache stores results of queries in the cache. What I don't understand is When does hibernate hit this cache? Let's say I've set up the second level cache but not the query caching. I want to cache my customers, there's 50000 of them. In what ways can I retrieve the customers from the