Pattern for a Singleton contaning lists
<p>I have various small lookup tables in my application where I don't want to query the database every time they are requested. So I want to only read these once when the singleton object is first requested.   The only issue I can see is if a user wants to edit records in these tables, I need to reset and reload the objects in the list again.</p>

<p>Is there a thread safe pattern for having a Singleton used for storing and retrieving lists of objects?</p>
