MoveCommand
Move the specified key from the currently selected DB to the specifieddestination DB. Note that this command returns 1 only if the key wassuccessfully moved, and 0 if the target key was already there or if thesource key was not found at all, so it is possible to use MOVE as a lockingprimitive.
Integer reply, specifically:
1 if the key was moved
0 if the key was not moved because already present on the target DB or was not found in the current DB.
-3 if the destination DB is the same as the source DB
-4 if the database index if out of range