Group By syntax while using Cross Join - sql

Question

i wish to apply a Group By condition to my SQL below so that the O/P will display POL# with GP.
select t.POl#, (DEB.CUSTD - CRED.CUSTC) AS GP
from (
(
select POL.SP_NUM POL#
, sum(D.AMT) AS CUSTD
from S_INVOICE D
, S_ASSET POL
where POL.ROW_ID = D.FN_ACCNT_ID
and POL.SP_NUM in ('000','111','222')
and D.DEBIT_TYPE = 'Customer'
group by POL.SP_NUM
) DEB
CROSS JOIN
(
select pol.SP_NUM POL#
, sum(C.AMT) AS CUSTC
from S_SRC_PAYMENT C
, S_ASSET POL
where POL.ROW_ID = C.ASSET_ID
and POL.SP_NUM in ('000','111','222')
and C.CG_DEDN_TYPE_CD = 'Customer'
group by POL.SP_NUM
) CRED
) t
group by t.POL#
When i execute the same I am getting "ORA-00933: SQL command not properly ended" error, where the cursor points to 't'
Kindly assist.
Expected O/P:
POL# GP
000 800
111 120
222 50
Appending Sample Data with explanation for better understanding of requirement:
Table 1:
S_ASSET
ROW_ID POL#
1 000
2 111
3 222
4 333
5 444
Table 2:
S_INVOICE (Debit Table)
FN_ACCNT_ID POL# DEBIT_TYPE AMT
1 000 Customer 10
1 000 Customer 10
1 000 Insurer 5
2 111 Customer 10
3 222 Customer 10
3 222 Insurer 5
5 444 Insurer 10
Table 3:
S_SRC_PAYMENT (Credit Table)
ASSET_ID POL# CG_DEDN_TYPE_CD AMT
1 000 Insurer 10
1 000 Insurer 10
1 000 Customer 5
2 111 Insurer 10
3 222 Insurer 5
3 222 Insurer 5
3 222 Customer 5
5 444 Customer 10
As per this query I will consider "Customer" records per POL# and SUM the AMT. (Every Debit for the Customer will Credit Insurer(s) per POL# & vice-versa)
Expected O/P (Sum of Debits - Sum of Credits) for a Customer per POL#
POL # AMT (GP)
000 15
111 10
222 5
333 0
444 -10

Answer 1

You obviously only want to get the deb and cred per s_asset and then aggregate so as to get the sums. You can do this without a join and subquery the sums directly instead:
select
sp_num as pol#,
sum(<get deb sum for the pol.row_id here>) - sum(<get cred sum for the pol.row_id here>)
from s_asset pol
where sp_num in ('000','111','222')
group by sp_num;
The complete query:
select
sp_num as pol#,
coalesce(sum(
(
select sum(deb.amt)
from s_invoice deb
where deb.fn_accnt_id = pol.row_id
and deb.debit_type = 'Customer'
)
), 0) -
coalesce(sum(
(
select sum(cred.amt)
from s_src_payment cred
where cred.asset_id = pol.row_id
and cred.cg_dedn_type_cd = 'Customer'
), 0)
) as gp
from s_asset pol
where sp_num in ('000','111','222')
group by sp_num;
The same with joins instead:
select
pol.sp_num as pol#,
coalesce(sum(deb.total), 0) - coalesce(sum(cred.total), 0) as gp
from s_asset pol
left join
(
select fn_accnt_id as pol_row_id, sum(deb.amt) as total
from s_invoice
where debit_type = 'Customer'
group by fn_accnt_id
) deb on deb.pol_row_id = pol.row_id
left join
(
select asset_id as pol_row_id, sum(amt) as total
from s_src_payment
where cg_dedn_type_cd = 'Customer'
group by asset_id
) cred on cred.pol_row_id = pol.row_id
group by pol.sp_num;

Answer 2

This syntax
from ( (select ...) CROSS JOIN (select ...) )
is invalid. A JOIN belongs to a FROM. So either of these would be correct:
from ( SELECT * FROM (select ...) CROSS JOIN (select ...) )
or
from (select ...) CROSS JOIN (select ...)
However, are you sure you want a CROSS JOIN at all? Both subqueries give you POL numbers plus data, bat rather than joining them on POL#, you cross join the results, so you get all POL# combinations instead.