SQL & PL/SQL

First, thanks for hitting the link to help

my question is about how to create tables in SQL oracle using Oracle database express edition for the following issue, and second about the building entity relationship

i want to represent a Leave Of Absence (LOA) system where there are two approval stages for LOA:
1- By the Managing Director (MD) who should approve first any LOA.
2- Second approval by the HR who check the available day balance for an employee. HR can not approve if the MD did not approve the LOA.

My confusion is about the Employee entity and the mechanism of the approval.
I have made a recursive relationship as managers are employee at the same time, but my problem is that HR are also employee and they should also approve the LOA after the MD. so, I was not so sure about the following:
1 . Should I make two recursive relationships for the entity of the employee to represent the relationship between Employee, Manger directors and HR personnel?
2. Is it much appropriate to name the relationship Manage or Approve as both seems valid? (I have made a separate entity for approval but also not sure if that is correct).
3. and finally, , how to create tables with PK and FK for the entity “employee” regarding the above mentioned conditioned?

Thanks in advance

Edited by: 825801 on Jan 5, 2011 11:55 AM