Oracle 21c

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CREATE TABLE device (PhoneCode, SeqID, Active, Token, CUSID ) AS
SELECT 'e29a5e1c695352b8', 3898, 'I', 'JYN8CYRVzaKWL-l_K',   50002 FROM DUAL UNION ALL
SELECT 'e29a5e1c695352b8', 3900, 'I', 'JYN8CYRVzaKWL-l_K',   50002 FROM DUAL UNION ALL
SELECT '741fb28bc72183e3', 3899, 'I', 'RU3ReKEw0yin9LxZWCO', 50002 FROM DUAL UNION ALL
SELECT '741fb28bc72183e4', 3901, 'A', 'RU3ReKEw0yin9LxZWCO', 50002 FROM DUAL;
4 rows affected

SELECT PHONECODE,
       SeqID,
       ACTIVE,
       Token
FROM   (
  SELECT d.*,
         ROW_NUMBER() OVER (PARTITION BY phonecode ORDER BY seqid DESC) AS rn
  FROM   device d
  WHERE  cusid = 50002
  AND    active = 'I'
)
WHERE  rn = 1;


PHONECODE
SEQID
ACTIVE
TOKEN


741fb28bc72183e3
3899
I
RU3ReKEw0yin9LxZWCO

e29a5e1c695352b8
3900
I
JYN8CYRVzaKWL-l_K


SELECT PHONECODE,
       MAX(SeqID) AS seqid,
       MAX(ACTIVE) KEEP (DENSE_RANK LAST ORDER BY SeqID) AS active,
       MAX(Token) KEEP (DENSE_RANK LAST ORDER BY SeqID) AS token
FROM   device
WHERE  cusid = 50002
AND    active = 'I'
GROUP BY phonecode;


PHONECODE
SEQID
ACTIVE
TOKEN


741fb28bc72183e3
3899
I
RU3ReKEw0yin9LxZWCO

e29a5e1c695352b8
3900
I
JYN8CYRVzaKWL-l_K

PHONECODE	SEQID	ACTIVE	TOKEN
741fb28bc72183e3	3899	I	RU3ReKEw0yin9LxZWCO
e29a5e1c695352b8	3900	I	JYN8CYRVzaKWL-l_K