Det, du har brug for, er en selvtilslutning ved at bruge den samme tabel TO GANGE i den samme forespørgsel, men forskelligt ALIAS...
select
t1.field,
t1.name,
t1.value as ThisIsYourParentKey,
t2.name as ParentName,
t2.value as GrandParentKey
from
YourTable t1
left join YourTable t2
on t1.value = t2.field
where
t1.name = 'a2'