I have an entity, for example employee(key employee ID), and every employee can have multiple responsibilities. Every responsibility can be tasked to multiple employees.
I have 3 options:
1) Create weak entity - responsibility when the key is responsibility name and employee ID from employee entity.
And those entities will a have many-to-many relation .
2) Make an employee-employee relation which will hold attribute responsibility.
3) Add attribute to employee as a key(ID, responsibility)
Is first option even possible!!! And what is the correct option.