An application programming interface (API), usually implemented in Java as an interface.

A set of facade classes that implement the interface and carry out persistence operations using a particular persistence technology (e.g., one set that uses Hibernate, another that uses JAXB). 

A factory method, or an injection mechanism, that is configured to pick the particular facade desired for the application. 

A good logging system to uncover problems when they arise.

A configuration file to select which facade class should be used.

public interface VehicleRepository { 
    public void create(Vehicle v);
    public Vehicle read(String registration);
    public void update(Vehicle v);
    public void delete(Vehicle v); 
}

public interface VehicleRepository { 
    public void newVehicle(Vehicle v);
    public Vehicle read(String registration);
    public void listAll();
    public void delete(Vehicle v); 
}

public interface VehicleRepository { 
    public void newVehicle(Vehicle v);
    public Vehicle get(String registration);
    public void save(Vehicle v);
    public void remove(Vehicle v); 
}

public interface VehicleRepository { 
    public void save(Vehicle v);
    public List<Vehicle> list(String registration);
    public void store(Vehicle v);
    public Vehicle get(String registration);
}

Lost features.

Errors can be lost or obscured.

There is no logging.

Patterns are over-used.