The description and optimization of query are proposed for advanced data query in process industrial data model . the method is easy to be realized . 3 對于流程工業數據的高級查詢提出了一種查詢表示和查詢優化的方法,這種方法易于實現并且具有很高的效率。
2 . the characteristics of process industrial real - time database model are introduced and a process industrial data model is built which adopts tags mapping method . the data model can handle the tag computation , lab ' s tag definition and process parameter store 2 )根據流程工業實時數據庫的應用背景,提出了以位號映射為特點的工程數據模型,這種模型支持位號間的計算關系,支持錄入功能和計算參數存儲。