Title: best practice for self join relation
this sql script show you how to join between employee table and it self, as you want to see employee name and his manager name (considering that the manger is employee too and is exists in the same table "employee")
use northwind
select emp.FirstName,managers.FirstName as 'direct manager name'
from Employees as emp join Employees as managers
on emp.ReportsTo = managers.EmployeeID
*this script runs on northwind database