Chen ER diagram modeling a human resources database with Person, Employee, Department, Project, and Address entities. The schema captures employee hierarchies through foreign keys linking employees to departments and persons, while a junction table Employee_Project tracks project assignments with role and hours allocated. This normalized structure demonstrates best practices for managing organizational data, separating concerns between personal information, employment records, and project allocations. Fork and customize this diagram on Diagrams.so to adapt it for your HR system, add additional attributes, or export as .drawio or PNG for documentation. The design supports complex queries on department budgets, manager hierarchies, and resource allocation across projects.