MySQL 8.0

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CREATE TABLE washtickets (
  ticket_id INT AUTO_INCREMENT PRIMARY KEY,
  user_id INT,
  used_at DATETIME,
  deleted_at DATETIME
);
INSERT INTO washtickets VALUES
    (1, 1, '2024-04-10 00:00:01',  NULL),
    (2, 1, '2024-04-10 00:00:02',  NULL),
    (3, 2, NULL,  NULL),
    (4, 3, '2024-04-10 00:00:01', '2024-04-10 00:00:01'),
    (5, 4, '2024-04-10 00:00:01',  NULL);

Records: 5  Duplicates: 0  Warnings: 0


SELECT
  MIN(ticket_id) AS ticket_id,
  user_id,
  MIN(used_at) AS used_at
FROM washtickets
WHERE deleted_at IS NULL
AND used_at IS NOT NULL
GROUP BY user_id
HAVING COUNT(*) = 1;


ticket_id
user_id
used_at


5
4
2024-04-10 00:00:01


SELECT
  MIN(w.ticket_id),
  w.user_id,
  w.used_at
  
FROM
  washtickets w JOIN
  (SELECT user_id, min(used_at) AS used_at FROM washtickets GROUP BY user_id) max_user
ON
  w.deleted_at IS NULL
  AND w.user_id = max_user.user_id
  AND w.used_at = max_user.used_at
GROUP BY w.user_id, w.used_at
HAVING COUNT(*) = 1
ORDER BY used_at ASC;


MIN(w.ticket_id)
user_id
used_at


1
1
2024-04-10 00:00:01

5
4
2024-04-10 00:00:01