ObjectContext class represents EntityContainer which you can see from XML view of Model1.edmx or from EDM property window. You can call this as context class.
This is the primary class for interacting with entity objects and database. An instance/object of the ObjectContext class encapsulates the connection to the database, metadata that describes the model, and an ObjectStateManager object that tracks objects during create, update, and delete operations.
With the help of this class you can access all the tables and columns in the underlying database.
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