select MgrID, EmpID, EmployeeName
from emp e
where MgrID in (select EmpID from emp b
where b.EmpID = 1)
For better, quicker answers, click on the following...
http://www.sqlservercentral.com/articles/Best+Practices/61537/
For better answers on performance questions, click on the following...
http://www.sqlservercentral.com/articles/SQLServerCentral/66909/