Case Statement that runs sql - sql

Question

I am applying a mask to data and believe the best way is to use a Case Statement. However, I need the case statement to run a sub query. When I pull data, it will either be a number or appear as 99999999999v999b:99999999999v999-
Using
TO_NUMBER(REGEXP_REPLACE(RD.subm_quantity, '^(\d+)(-)?$', '\2\1'))/1000 as "Submitted_Quantity"
This will convert it to a number. So if 00000000100000 is present, it will convert to 100
However, I need a case to not divide when not needed. To determine if I need to divide, I need to add a rule in the below sql:
if the result is 99999999999v999b:99999999999v999-, apply the conversion;
if not, just output RD.subm_quantity.
How can I get a case statement to run a query?
Running in TOAD for Oracle:
select m.mask
FROM Valiuser.ivd_mapping m,
Valiuser.ivd_mappingset s,
Valiuser.ivd_mapping_record r,
Valiuser.ivd_transaction_file tf,
VALIUSER.ivd_transaction_record_details RD
WHERE s.mappingset_id = r.mappingset_id
AND r.mapping_record_id = m.mapping_record_ID
AND m.repository_column_id = '34'
AND s.mappingset_id = tf.MAPPINGSET_ID
AND rd.file_id = tf.file_id
AND rd.TRANSACTION_RECORD_ID =

Answer 1

If the mask and original subm_quantity are both available from the query you showed, which seems to be the same as that includes the rd table you're referencing in the conversion, then I think you want something like this:
case when m.mask = '99999999999v999b:99999999999v999-'
then TO_NUMBER(REGEXP_REPLACE(rd.subm_quantity, '^(\d+)(-)?$', '\2\1')) / 1000
else rd.subm_quantity
end as "Submitted_Quantity"
rather than a subquery. So plugged into your current query that would make it:
SELECT
case when m.mask = '99999999999v999b:99999999999v999-'
then TO_NUMBER(REGEXP_REPLACE(rd.subm_quantity, '^(\d+)(-)?$', '\2\1')) / 1000
else rd.subm_quantity
end as "Submitted_Quantity"
FROM
Valiuser.ivd_mapping m,
Valiuser.ivd_mappingset s,
Valiuser.ivd_mapping_record r,
Valiuser.ivd_transaction_file tf,
Valiuser.ivd_transaction_record_details rd
WHERE
s.mappingset_id = r.mappingset_id
AND r.mapping_record_id = m.mapping_record_ID
AND m.repository_column_id = '34'
AND s.mappingset_id = tf.mappingset_id
AND rd.file_id = tf.file_id
AND rd.Transaction_Record_Id = <?>
or with modern join syntax instead of the old version, something like:
SELECT
case when m.mask = '99999999999v999b:99999999999v999-'
then TO_NUMBER(REGEXP_REPLACE(rd.subm_quantity, '^(\d+)(-)?$', '\2\1')) / 1000
else rd.subm_quantity
end as "Submitted_Quantity"
FROM Valiuser.ivd_mapping m
JOIN Valiuser.ivd_mapping_record r ON r.mapping_record_id = m.mapping_record_ID
JOIN Valiuser.ivd_mappingset s ON s.mappingset_id = r.mappingset_id
JOIN Valiuser.ivd_transaction_file tf ON tf.mappingset_id = s.mappingset_id
JOIN Valiuser.ivd_transaction_record_details rd ON rd.file_id = tf.file_id
WHERE m.repository_column_id = '34'
AND rd.transaction_record_id = <?>