A shared-nothing database management system employs a method of adding and removing a database server without significantly affecting the processing performance for accessing a table from a user or an application. A piston-shaped valve needle is contained in the bore in a longitudinally sliding fashion and has an essentially conical valve sealing surface by means of which the valve needle cooperates with the valve seat in order to control the at least one injection opening. Additionally, the transmit PSD may be adapted based, at least in part, on a total power capability associated with a transmitter. In a particular embodiment, the plug assembly further includes a biasing member positioned between the body of the plug and the back side of the shield member to operatively interact with the shield member to prevent electrical current flow and during operation the shield member may slide over the body and operatively engage the actuator to allow electrical current flow. The trench defines a section of the first layer stacked with a section of the second layer.