Introduction - If you have any usage issues, please Google them yourself
Using the concept of structure design is entity attribute analysis. From the analysis of the general physical properties, from the analysis of the concept of a unit of affairs activity began, first identify needs analysis is provided in the entity and the relationship between entities, establish a preliminary data model frame, then gradually in the method of refinement and necessary description attribute, formed a complete local model, called the user view of these views, finally add a unified integrated data model