er-diagram.txt

erDiagram
    EMPLOYEES {
        INT emp_no PK
        VARCHAR first_name
        VARCHAR last_name
        VARCHAR job_title
        DECIMAL basic_salary
        INT department_id FK
    }
    
    DEPARTMENTS {
        INT department_id PK
        VARCHAR department_name
        INT manager_id FK
    }

    PROJECTS {
        INT project_id PK
        VARCHAR project_name
        DATE start_date
        DATE end_date
        INT department_id FK
    }

    EMPLOYEE_PROJECT {
        INT emp_no FK
        INT project_id FK
        DECIMAL hours_worked
    }

    SALARIES {
        INT emp_no FK
        DATE salary_date PK
        DECIMAL basic_salary
        DECIMAL da
        DECIMAL hra
        DECIMAL gross_salary
        DECIMAL tax
        DECIMAL net_salary
    }

    EMPLOYEES ||--o{ DEPARTMENTS: "department_id"
    DEPARTMENTS ||--o{ PROJECTS: "department_id"
    EMPLOYEES ||--o{ SALARIES: "emp_no"
    EMPLOYEES ||--o{ EMPLOYEE_PROJECT: "emp_no"
    PROJECTS ||--o{ EMPLOYEE_PROJECT: "project_id"
    EMPLOYEES ||--o{ DEPARTMENTS: "manager_id"