DECLARE @sys_user TABLE 
	(UserId bigint
	,FRST_NM varchar(100)
	,LST_NM varchar(100)
	,APROV_ID bigint)
	
Insert into @sys_user
Select 800000000, 'Dave', 'Smith', NULL
UNION Select 810000000, 'Michael', 'Chak',800000000
UNION Select 811000000, 'David', 'Boon',810000000
UNION Select 811100000, 'Glen','Macgrath',811000000
UNION Select 811110000, 'Alex', 'Boon',811100000
UNION Select 811111000, 'Jim', 'Foley',811111000
UNION Select 821000000,'Stephan', '',800000000

DECLARE  @UserId BIGINT=800000000

select * from @sys_user

;With submenu (UserId,Name,APROV_ID,lvl)
AS
(
	Select UserId, FRST_NM + ' '+LST_NM as Name,APROV_ID, 0 lvl
	From @sys_user
	Where UserId=@UserId
	Union ALL Select
		su.UserId
		,su.FRST_NM + ' '+su.LST_NM
		,su.APROV_ID
		,sm.lvl+1
	From @sys_user su
		Join submenu sm ON su.APROV_ID=sm.UserId
)
Select SPACE(lvl*2)+STR(UserID) + '||  '+Name,lvl
From submenu
Order by UserId