CTE with Merge statement in Oracle - oracle

Question

I am trying to create a CTE to use the same in Merge statement in Oracle, but facing error so please have a look and help me out, earlier we were using subquery instead CTE but to enhance the response time of query I am trying CTE so please suggest me another approach to enhance the response time of query. Curious to know whether oracle supports CTE and Merge statement together as I did in below code.
With TRANS_HIST
As
(Select
NUMERO_DE_CUENTA,
TRANS_DATETIME,
Lag(TRANS_DATETIME, 1)
over
(
ORDER BY NUMERO_DE_CUENTA,TRANS_DATETIME) lag_trans_datetime
FROM db_fraud_bpd.tbl_event_new_transaction_h
)
MERGE
INTO DB_FRAUD_BPD.TBL_RT_FEATURES_TEMP t1
USING
(
SELECT
RTTEMP.ACCOUNT_NUMBER,
RTTEMP.TRANS_DATETIME,
CASE WHEN STDDEV(TRANS_HIST.TRANS_DATETIME - TRANS_HIST.lag_trans_datetime) = 0 THEN NULL
WHEN ROUND(( ( (RTTEMP.TRANS_DATETIME - Max(TRANS_HIST.TRANS_DATETIME)) - Avg(TRANS_HIST.TRANS_DATETIME - TRANS_HIST.lag_trans_datetime)) / STDDEV(TRANS_HIST.TRANS_DATETIME -TRANS_HIST.lag_trans_datetime)),3) >999999999999999 THEN 999999999999999
WHEN ROUND(( ( (RTTEMP.TRANS_DATETIME - Max(TRANS_HIST.TRANS_DATETIME)) - Avg(TRANS_HIST.TRANS_DATETIME - TRANS_HIST.lag_trans_datetime)) / STDDEV(TRANS_HIST.TRANS_DATETIME -TRANS_HIST.lag_trans_datetime)),3) <-99999999999999 THEN -99999999999999
ELSE ROUND(( ( (RTTEMP.TRANS_DATETIME - Max(TRANS_HIST.TRANS_DATETIME)) - Avg(TRANS_HIST.TRANS_DATETIME - TRANS_HIST.lag_trans_datetime)) / STDDEV(TRANS_HIST.TRANS_DATETIME -TRANS_HIST.lag_trans_datetime)),3)
END AS TIME_DELTA_ZSCORE_PAST_90_DAYS
FROM TRANS_HIST
right outer join
db_fraud_bpd.tbl_rt_features_temp RTTEMP
ON Cast(RTTEMP.account_number AS INTEGER) = Cast(TRANS_HIST.NUMERO_DE_CUENTA AS INTEGER)
WHERE
(
TRANS_HIST.TRANS_DATETIME < RTTEMP.TRANS_DATETIME
AND TRANS_HIST.TRANS_DATETIME >= (RTTEMP.TRANS_DATETIME-90)
)
or TRANS_HIST.TRANS_DATETIME IS NULL
GROUP BY
RTTEMP.account_number,
RTTEMP.TRANS_DATETIME
)TEMP
ON (t1.TRANS_DATETIME=TEMP.TRANS_DATETIME AND t1.ACCOUNT_NUMBER=TEMP.ACCOUNT_NUMBER)
WHEN MATCHED
THEN UPDATE
SET t1.TIME_DELTA_ZSCORE_PAST_90_DAYS = TEMP.TIME_DELTA_ZSCORE_PAST_90_DAYS

Answer 1

You may use CTE in the merge statement, but in the rigth position in the merge subquery.
See example below
merge into tab
using (with t as (
select 1 id, 'x' x from dual union all
select 2 id, 'y' x from dual)
select * from t) b
on (tab.id = b.id)
when matched then
update set tab.x = b.x
when not matched then
insert (id, x)
values (b.id, b.x);

Answer 2

Don't use TRANS_HIST as a CTE, but as a subquery.
MERGE INTO DB_FRAUD_BPD.TBL_RT_FEATURES_TEMP t1
USING ( SELECT RTTEMP.ACCOUNT_NUMBER,
RTTEMP.TRANS_DATETIME,
CASE
WHEN STDDEV (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime) =
0
THEN
NULL
WHEN ROUND (
( ( ( RTTEMP.TRANS_DATETIME
- MAX (TRANS_HIST.TRANS_DATETIME))
- AVG (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime))
/ STDDEV (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime)),
3) >
999999999999999
THEN
999999999999999
WHEN ROUND (
( ( ( RTTEMP.TRANS_DATETIME
- MAX (TRANS_HIST.TRANS_DATETIME))
- AVG (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime))
/ STDDEV (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime)),
3) <
-99999999999999
THEN
-99999999999999
ELSE
ROUND (
( ( ( RTTEMP.TRANS_DATETIME
- MAX (TRANS_HIST.TRANS_DATETIME))
- AVG (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime))
/ STDDEV (
TRANS_HIST.TRANS_DATETIME
- TRANS_HIST.lag_trans_datetime)),
3)
END AS TIME_DELTA_ZSCORE_PAST_90_DAYS
FROM (SELECT NUMERO_DE_CUENTA,
TRANS_DATETIME,
LAG (TRANS_DATETIME, 1)
OVER (
ORDER BY NUMERO_DE_CUENTA, TRANS_DATETIME) lag_trans_datetime
FROM db_fraud_bpd.tbl_event_new_transaction_h)
TRANS_HIST
RIGHT OUTER JOIN db_fraud_bpd.tbl_rt_features_temp RTTEMP
ON CAST (RTTEMP.account_number AS INTEGER) =
CAST (TRANS_HIST.NUMERO_DE_CUENTA AS INTEGER)
WHERE ( TRANS_HIST.TRANS_DATETIME < RTTEMP.TRANS_DATETIME
AND TRANS_HIST.TRANS_DATETIME >=
(RTTEMP.TRANS_DATETIME - 90))
OR TRANS_HIST.TRANS_DATETIME IS NULL
GROUP BY RTTEMP.account_number, RTTEMP.TRANS_DATETIME) TEMP
ON ( t1.TRANS_DATETIME = TEMP.TRANS_DATETIME
AND t1.ACCOUNT_NUMBER = TEMP.ACCOUNT_NUMBER)
WHEN MATCHED
THEN
UPDATE SET
t1.TIME_DELTA_ZSCORE_PAST_90_DAYS = TEMP.TIME_DELTA_ZSCORE_PAST_90_DAYS