with hier as 
(

SELECT 1 id,11 par_id,'MAIN' code from dual
UNION
SELECT 11,21,'MAIN' from dual
UNION
SELECT 21,31,'MAIN' from dual
UNION
SELECT 31,41,'MAIN' from dual
UNION
SELECT 41,NULL,'MAIN' from dual
union
SELECT 2,22,'MAIN' from dual
UNION
SELECT 22,32,'MAIN' from dual
UNION
SELECT 32,NULL,'MAIN' from dual
UNION
SELECT 5,15,'MAIN' from dual
UNION
SELECT 15,31,'MAIN' from dual
)
,product as
(
SELECT 1 id,'продукт1' lname from dual
UNION
SELECT 11,'продукт11' from dual
UNION
SELECT 21,'продукт21' from dual
UNION
SELECT 31,'продукт31' from dual
UNION
SELECT 41,'продукт41' from dual
UNION
SELECT 2,'продукт2' from dual
union
SELECT 22,'продукт22' from dual
UNION
SELECT 32,'продукт32' from dual
UNION
SELECT 5,'продукт5' from dual
UNION
SELECT 15,'продукт15' from dual
)


,hh AS 
(
SELECT h.id,h.par_id,p.lname,h.code
FROM hier h
LEFT JOIN product p ON p.id=h.id
WHERE h.code='MAIN'
)

SELECT COALESCE(e.id,d.id,c.id,b.id,a.id) id
,a.id product_lev1_id, a.lname  product_lev1_name
,COALESCE(b.id,a.id) product_lev2_id,COALESCE(b.lname,a.lname) product_lev2_name
,COALESCE(c.id,b.id,a.id) product_lev3_id,COALESCE(c.lname,b.lname,a.lname) product_lev3_name
,COALESCE(d.id,c.id,b.id,a.id) product_lev4_id,COALESCE(d.lname,c.lname,b.lname,a.lname) product_lev4_name
,COALESCE(e.id,d.id,c.id,b.id,a.id) product_lev5_id,COALESCE(e.lname,d.lname,c.lname,b.lname,a.lname) product_lev5_name
FROM hh a
LEFT JOIN hh b ON a.id=b.par_id
LEFT JOIN hh c ON b.id=c.par_id
LEFT JOIN hh d ON c.id=d.par_id
LEFT JOIN hh e ON d.id=e.par_id
WHERE a.par_id IS NULL