Oracle PLSQL interview questions - 2

1. From an Employee table, how will you display the record which has a maximum salary?
2. What is the difference between the Primary and Foreign key?
3. How will you delete a particular row from a Table?
4. How will you select unique values from a list of records?
5. What is meant by Join? What are the different types of Joins available? Explain.
6. overloading of stored procedure is possible in oracle?