You are implementing a Windows Communication Foundation (WCF) service that uses Entity Framework. Several service methods will return entities; other methods will write changes made to entities to the database. You need to decide when to create the ObjectContext and how to configure the ObjectContext to use minimal memory.

What should you do?

To minimize memory usage and complexity, create an ObjectContext within each service method. Execute queries with the MergeOption set to NoTracking. Memory used by the ObjectContext will be disposed after the object is returned. Setting the MergeOption to NoTracking will minimize memory usage before the ObjectContext is disposed.

If you set MergeOption to AppendOnly, the ObjectContext's ObjectStateManager will track object state. This tracking is not needed. Set MergeOption to NoTracking instead.