Трюк дня. Максимальное значение без self-join. Решение

SELECT *
FROM
(
SELECT
e.*,
CASE WHEN (salary = MAX (salary) OVER (PARTITION BY t_id)) THEN 'Y' ELSE 'N' END AS max_num_id
FROM
employee e
) DAT2
WHERE max_num_id = 'Y';

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