Help in designing mysql table for large project
If there is a possibility of an employee to work in many companies such as Advisor or Instructor, the above designs will fail. 
There are possibilitites where one employee can work in more than one company. 

So the perfect design would be the below

Company_Id   Company_Name
   1          Aaaa
   2          Bbbb 
   3          cccc


Employee_Id   Employee_Name
   11          A
   22          B 
   33          c


Company_Id   Employee_Id
   1          11
   2          22
   3          33
   3          22

This works in both the ways. One employee can work in many companies and many companies can have same employee. Many to Many relationship .