Oracle 23c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
ALTER SESSION SET NLS_TIMESTAMP_FORMAT = 'YYYY-MM-DD HH24:MI:SS.FF';
CREATE TABLE table_name (COMMENT_ID, TIMESTAMP, STATUS, USER_NAME_1, USER_NAME_2) AS
SELECT 'COM_006273', TIMESTAMP '2022-02-13 13:56:00', 'CLOSED', 'John Doe',    NULL FROM DUAL UNION ALL
SELECT 'COM_006273', TIMESTAMP '2022-02-13 08:45:00', 'OPEN',   'Paul Jacobs', 'John Doe' FROM DUAL UNION ALL
SELECT 'COM_005091', TIMESTAMP '2022-02-11 16:53:00', 'CLOSED', 'Mark Clarke', NULL FROM DUAL UNION ALL
SELECT 'COM_005091', TIMESTAMP '2022-02-11 09:02:00', 'OPEN',   'Paul Jacobs', 'John Doe' FROM DUAL;
4 rows affected

SELECT comment_id
FROM   table_name
       MATCH_RECOGNIZE(
         PARTITION BY comment_id
         ORDER BY timestamp
         PATTERN (open invalid_closed)
         DEFINE
           open           AS  status = 'OPEN',
           invalid_closed AS  status = 'CLOSED'
                          AND user_name_1 IN (open.user_name_1, open.user_name_2)
       )


COMMENT_ID


COM_006273


SELECT o.comment_id
FROM   table_name o
       INNER JOIN table_name ic
       ON     o.comment_id =  ic.comment_id
          AND o.timestamp  <= ic.timestamp 
          AND ic.user_name_1 IN (o.user_name_1, o.user_name_2)
WHERE  o.status  = 'OPEN'
AND    ic.status = 'CLOSED';


COMMENT_ID


COM_006273


SELECT *
FROM   table_name
       UNPIVOT (
         user_name FOR type IN (
           user_name_1 AS 1,
           user_name_2 AS 2
         )
       )
       PIVOT (
         MAX(timestamp)
         FOR (status, type) IN (
           ('OPEN', 1) AS ts_o1,
           ('OPEN', 2) AS ts_o2,
           ('CLOSED', 1) AS ts_c1
         )
       )
WHERE  ts_o1 < ts_c1
OR     ts_o2 < ts_c1;


COMMENT_ID
USER_NAME
TS_O1
TS_O2
TS_C1


COM_006273
John Doe
null
2022-02-13 08:45:00.000000000
2022-02-13 13:56:00.000000000