Based on the scenario you've provided, we have three entities: Technician, Notebook, and Project.
- A Technician uses exactly one Notebook for each Project.
- Each Notebook belongs to one Technician for each Project.
- A Technician may work on many Projects and maintain different Notebooks for different Projects.
This scenario describes a ternary relationship because it involves three entities that are all interrelated. The degree of the relationship is therefore 3 (ternary).
Here's a simplified way to visualize the E-R model:
Technician ----uses----> Notebook ----for----> Project
^ |
| |
|------------------maintains-----------------|
In this model:
- The 'uses' relationship connects Technician and Notebook.
- The 'for' relationship connects Notebook and Project.
- The 'maintains' relationship connects Technician and Project.
All three entities are interconnected, creating a ternary relationship.