select
d.id,d.cid,d.name , a.name , b.name, c.name
from
d
inner join c on d.cid=c.id
inner join b on c.bid=b.id
inner join a on b.aid=a.id
d.id,d.cid,d.name , a.name , b.name, c.name
from
d
inner join c on d.cid=c.id
inner join b on c.bid=b.id
inner join a on b.aid=a.id
select d.id,d.cid,d.name , a.name , b.name, c.name
from a
inner join b on b.id=a.bid
inner join c on b.id=c.bid
inner join d on c.id=d.cid
where a.name = 'a1'