peoplesoft function PSTREENODE 通过 deptid 获得部门树 一级部门 code

create or replace function ht_gettopdeptid(deptid in varchar)
  return varchar2 is
  r   varchar2(1024);
  c   int;
  m   varchar2(20);
  r_f varchar2(1024);

begin
  select  a.tree_level_num, a.parent_node_name,a.tree_node
    into c, r,m
    from pstreenode a
   where a.tree_name = 'DEPT_SECURITY'
     and a.tree_node = deptid and A.EFFDT =(SELECT MAX(A_ED.EFFDT) FROM pstreenode A_ED WHERE A.tree_node = A_ED.tree_node);
     if c<3
       then return null;
       end if;
  if
          c= 3
           then return m;
       else
         while(c<>3) loop
         select a.tree_level_num, a.parent_node_name
        into c, r
        from pstreenode a
       where a.tree_name = 'DEPT_SECURITY'
         and a.tree_node = m and A.EFFDT =(SELECT MAX(A_ED.EFFDT) FROM pstreenode A_ED WHERE A.tree_node = A_ED.tree_node);
             select a.tree_level_num, a.parent_node_name,a.parent_node_name
        into c, r,m
        from pstreenode a
       where a.tree_name = 'DEPT_SECURITY'
         and a.tree_node = m and A.EFFDT =(SELECT MAX(A_ED.EFFDT) FROM pstreenode A_ED WHERE A.tree_node = A_ED.tree_node);
      if c = 4 then
        return r;
      end if;
    end loop;
  end if;

end ht_gettopdeptid;