Casting Decimals in Oracle

Question

This code worked as a query in DB2, but I am not sure what the syntax is for casting decimals in Oracle:
decimal(decimal(A.record_count-A.generic_count-A.unusable_count,10,2) / decimal(B.record_count,10,2) * 100,10,2) usable_percent
The full query is:
SELECT B.load_date,
B.dsrc_id,
C.dsrc_code,
A.table_seq,
A.table_name,
A.record_type,
B.record_count total_records,
A.record_count,
A.generic_count,
A.unusable_count,
A.record_count-A.generic_count-A.unusable_count usable_count,
decimal(decimal(A.record_count-A.generic_count-A.unusable_count,10,2) / decimal(B.record_count,10,2) * 100,10,2) usable_percent
FROM (select load_id, table_seq, table_name, record_type,sum(record_count) record_count, sum(generic_count) generic_count, sum(unusable_count) unusable_count
from umf_sum_quality group by load_id, table_seq, table_name, record_type) A,
(select load_id, dsrc_id, load_date, sum(record_count) record_count
from umf_load_sum group by load_id, dsrc_id, load_date) B,
dsrc_code C
WHERE B.load_id = A.load_id and C.dsrc_id = B.dsrc_id
ORDER BY B.load_date desc, B.dsrc_id, A.table_seq, A.table_name, A.record_type

Answer 1

If you are running on isqlplus or sql *plus
set numformat 99999999999999999999.99999999999999but all numeric values follows the above format.
If the expression's output comes with huge decimals then you can use the Round Function
Round (Expression,N)
N- No of digits required in the decimal area.
Kanish