Application Data Model

A data model is the database concept representing the application entities, entity attributes, and entity relations persisted in the database schema.

The entities (components) specified for the application are:

• Employee

  This entity manages the records for the employee instances. The own attributes of this entity are employeeId , firstName , lastName , email , and so on. It also has the relationship attributes skills , projectsLeadByEmployee , and projectsByParticipant .

• Project

  This entity is responsible for the records of the project instances. Its own attributes are projectId , title , description , and so on. It also has the relationship attributes employees , leader , and skills .

• Skill

  This entity manages the database entries for the skill instances. The attributes are skillId , language , and name .

The relationships that connect the entities within this data model are the following:

• Project - Employees

  Bidirectional many-to-many relationship for regular employees, and bidirectional one-to-one relationship for employees designated as project leads.

• Project - Skill

  Unidirectional many-to-many relationship.

• Employee - Skill

  Unidirectional many-to-many relationship.