Add a new Task, and if its id already exist generate a new id.

Add a new Person to the DB, and if its id already exist generate a new id.

Get the Tasks of an exists Person from the DB.

Delete only an exists person.

Get the Task with the Same id, and only if exist delete it.

Find the Person with the same id, and edit his details in the DB.

Find the Task with the same id, and edit his details in the DB.

Only if the new ownerId is of an exists Person in the DB, update the task.

If the Task id exist in the DB update its status.