I would suggest some changes to the recommended schema. People's names should always be a minimum of two fields. I added a date to the salary table so you can tell when the salary was implemented. I also added a unique index on the Staff_ID and SalaryStartDate because it doesn't make any sense to allow multiple salary records for the same date. The second should supersede the first.
Staff table
Staff_ID(Primary Key)
FirstName
LastName
Contact
Address.....
Salary
Salary_ID(Primary Key)
Staff_ID (Foreign Key), (UniqueIDX, field1)
SalaryStartDate (UniqueIDX field2)
Salary