Delete Parent record if child is not present

Question

I am creating menu and submenus in a table variable. ( Typical parent child records in the same table) ParentID coll is null for all Top menus. And for their child ParentID

Answer 1

A single statement like this should do it (as an alternative to using exists):

delete p
from
    tblMenu p
    left join tblMenu c on p.ID = c.ParentID
where 
    p.ParentID is null --Ensures that the item to delete is at the top
    and c.ParentID is null --Finds top level items with no children