Hi dear members

i have aproblem please help me.........please
My problem is self-referencing .That mean,

I have table Emp like

Empid ename deptno mgr_empid sal

These are the attributes of my table.

The mgr_empid attribute should accept only the values fo empid attribute.
that mean i have to use empid as reference to mgr_empid.
How can i do it on the same table .
please help me......
thank you.