What is view and view all in permission sets. What are sharing rules and how they differ from permission sets. What is apex asynchronous and synchronous. What is batch and queuable apex difference and when to use one. How will you proceed to send 4 million record sharing with other system through RESTAPI. Hands on integration. Write a trigger to proove yourself at last based on this scenario where an account should have only one contact and if user tried to add other contacts on this account than it should throw error.

What is sharing rules and how you give access through this to users and not through permission sets.