Question

Based on the given requirements, the following relational notation for the ERD diagram can be developed:

Devices table:
- device_id (primary key)
- location
- device_type
- min_cash_amount (for ABMs only)
Maintenance_Routines table:
- routine_id (primary key)
- device_id (foreign key)
- employee_id (foreign key)
- start_date
- end_date
- description
- status
Employees table:
- employee_id (primary key)
- supervisor_id (foreign key, allows nulls) - trn - first_name - middle_initial - last_name - dob
Employees table:
- employee_id (primary key)
- supervisor_id (foreign key, allows nulls)
- trn
- first_name
- middle_initial
- last_name
- dob
- age
- mobile_number
Supervisors table:
- supervisor_id (primary key)
- start_date
- end_date
- employee_id (foreign key) Note: The "Supervisors" table is used to create a many-to-many relationship between employees and their supervisors. An employee can have multiple supervisors during their employment and a supervisor can supervise multiple employees at different times. The "start_date" and "end_date" columns are used to keep track of the time period during which an employee was assigned to a specific supervisor.

Answer 1

The given requirements provide an example of an ERD diagram for a database, including tables for devices, maintenance routines, employees, and supervisors.

Step-by-step explanation:

ERD Diagram Example

The given requirements outline the structure of an Entity-Relationship Diagram (ERD) for a database. The ERD represents the relationships between tables in a relational database design. The given example includes three tables: Devices, Maintenance_Routines, and Employees.The Devices table contains information about different devices, such as their ID, location, type, and minimum cash amount. The Maintenance_Routines table tracks the maintenance routines with details like routine ID, device ID, employee ID, start and end dates, description, and status. The Employees table holds information about employees, including their ID, supervisor ID, TRN, first name, middle initial, last name, date of birth, age, and mobile number. Finally, there is a Supervisors table to represent the many-to-many relationship between employees and their supervisors, which includes the supervisor ID, start and end dates, and employee ID.

Summary

The given requirements provide an example of an ERD diagram for a database. It includes tables for devices, maintenance routines, employees, and supervisors, capturing important information about each entity and their relationships.