PURPOSE: To suppress a delay of a whole system owing to a delay in production of a part to a minimum without stopping a production line even when production of a specified part is delayed by setting a whole production system to a state in which picking not executed in a past is performed in highest priority at all times.

CONSTITUTION: When a corresponding part is absent at a stock lane, data at the head of a main register 60c is transferred to a subregister 60d and data next to the head of the main register 60c is fetched. When data is present at the subregister 60d, the interior of the subregister 60d is retrieved. When data corresponding to a part present at a stock lane is stored in the subregister 60d, the data is outputted. This constitution holds picking indication for a delayed part in highest priority without stopping a production line and continues production in a state to suppress a delay in a production plan to a minimum.