I have key value database that functions as though all keys exist, start with an empty/default value, and hold whatever value they are assigned. Of course implementation wise only keys with a non-empty/non-default values are stored; meaning non existent keys are created when set and keys set to an empty/default value are remove. This removes the need for an add or remove operation by removing nonexistence.
My question is: does this concept of a key value database without nonexistence have terminology for it?