In the person information system, the information of all people is the attributes of the person object, such as firstname, lastname, and card.
Employee information: the position of a person in a company, for example, department or level.
In the design of most information systems, the person and employee are designed together, which is generally enough, but it is insufficient to deal with some situations.
1. Entry-> resignation-re-entry-> resignation
2. The Group Company and branch offices have independent accounting, and some individuals have multiple roles.
If we use the person-Employee separation design method, these problems will be solved.
Employee can be defined as a situation in which a person works during a period of time.
For Question 1: three employees can be used to indicate the period of entry-> resignation respectively.
Question 2: The work of a branch can be represented by an employee.
This design is not only in line with the actual situation, but also clear from the statistical point of view.