SQL分組排序去重復的小實例

復制代碼 代碼如下:
SELECT
    *
FROM
    (
        SELECT
            userid,
            classid,
            remark,
            ROW_NUMBER () OVER (
                PARTITION BY userid,
                classid
            ORDER BY
                addtime DESC
            ) AS row_bank
        FROM
            Eng24VIPCourseIntention
    ) AS ta
WHERE
    row_bank = 1

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 PARTITIONBYuserid,classid 這裡是按什麼分組， 注意一下。