Union among multiple select queries with full outer join

Question

Hello everyone,
I have 3 different select queries (used FULL Outer Join) which work fine. Now I want to add Union to the results among them and pick the selected columns from each query in the final result. while doing so, I am getting an error as "right parenthesis missing". I am quite sure, it is not the real cause. I guess might be issue with the query structure.
select j.pod, j.hostname, portal.hostname,saasc.hostname,a3s.hostname from -- * from
Select J.Pod,J.Hostname, P.Pod Portal_Pod,P.Hostname Portal_Hostname
From Total_Pod J
full outer join Portal_Tmp P On (J.Pod = P.Pod And J.Hostname = P.Hostname) as portal
Union
Select J.Pod,J.Hostname, s.Pod saasc_Pod,s.Hostname saasc_Hostname
From Total_Pod J
full outer join Saasc_Tmp S  On (J.Pod = s.Pod And J.Hostname = s.Hostname) as saasc
Union
Select J.Pod,J.Hostname, a.Pod a3s_Pod,a.Hostname a3s_Hostname
From Total_Pod J
Full Outer Join A3s_Tmp A  On (J.Pod = A.Pod And J.Hostname = A.Hostname) as a3s
)p.s: select * from (INNER QUERY); also does not work.
Any help appreciated.
Thanks in advance.

Answer 1

With T as
(Select J.Pod,J.Hostname, P.Pod Portal_Pod,P.Hostname Portal_Hostname
From Total_Pod J
full outer join Portal_Tmp P On (J.Pod = P.Pod And J.Hostname = P.Hostname) ),
U as
(Select J.Pod,J.Hostname, s.Pod saasc_Pod,s.Hostname saasc_Hostname
From Total_Pod J
full outer join Saasc_Tmp S  On (J.Pod = s.Pod And J.Hostname = s.Hostname) ),
V as
(Select J.Pod,J.Hostname, a.Pod a3s_Pod,a.Hostname a3s_Hostname
From Total_Pod J
Full Outer Join A3s_Tmp A  On (J.Pod = A.Pod And J.Hostname = A.Hostname) )
Select T.Pod,T.Hostname,nvl(T.Portal_Hostname,'Not Available') portal,nvl(U.Saasc_Hostname,'Not Available') saasc,NVL(V.A3s_Hostname,'Not Available') a3s From T,U,V
Where T.Pod = U.Pod
And U.Pod = V.Pod
And T.Hostname = U.Hostname
And U.Hostname = V.Hostname