with recursive req AS (
SELECT t.id, t.parent_id, t.level, t.desc, t.id as zlevel
	from test_case t
	where t.id in (4,7)
union
	SELECT l.id, l.parent_id, l.level, l.desc, zlevel
	from test_case l
	join req on l.id = req.parent_id
)
 select 
 max(CASE WHEN level = 1 THEN id ELSE 0 END) as l1,
max(CASE WHEN level = 1 THEN req.desc ELSE 'none' END) as l1,
max(CASE WHEN level = 2 THEN id ELSE 0 END) as l2,
max(CASE WHEN level = 2 THEN req.desc ELSE 'none' END) as l2,
max(CASE WHEN level = 3 THEN id ELSE 0 END) as l3,
max(CASE WHEN level = 3 THEN req.desc ELSE 'none' END) as l3,
max(CASE WHEN level = 4 THEN id ELSE 0 END) as l4,
max(CASE WHEN level = 4 THEN req.desc ELSE 'none' END) as l4
 from req
 group by zlevel
 order by zlevel;