Fields are the basic units of data storage, and each field typically contains information pertaining to one aspect or attribute of the entity described by the database.
域是数据存储的基本单位，每个域一般含有由数据库描述的属于实体的一个方面或一个特性的信息。
2
The system can provide the drawing of basic graphic element, the connection with attribute database, and meet the basic need of the field management.