postgresql 取出分组中最大的几条数据

WITH Name AS (
    SELECT
        *
    FROM
        (
            SELECT
                xzqdm,
                SUBSTRING (zldwdm, 1, 9) xzdm,
                COUNT (*) sl
            FROM
                sddltb_qc
            WHERE
                xzqdm IN ('130432', '210604')
            GROUP BY
                xzqdm,
                SUBSTRING (zldwdm, 1, 9)
        ) AS A
    ORDER BY
        xzqdm,
        xzdm,
        sl
) SELECT
    xzqdm,
    xzdm,
    sl
FROM
    (
        SELECT
            *, ROW_NUMBER () OVER (
                PARTITION BY xzqdm
                ORDER BY
                    sl DESC
            ) AS Row_ID
        FROM
            Name
    ) AS A
WHERE
    Row_ID <= 2
ORDER BY
    xzqdm

其中【select * from (select xzqdm,substring(zldwdm,1,9) xzdm,count(*) sl from sddltb_qc where xzqdm in ('130432','210604') group by xzqdm,substring(zldwdm,1,9)) as a order by xzqdm,xzdm,sl】执行结果：

添加行序号：ROW_NUMBER () OVER (ORDER BY A.bsm ASC) AS 序号

分组添加序号：ROW_NUMBER () OVER (PARTITION BY xzqdm ORDER BY A.bsm ASC) AS 序号

 

转载于:https://www.cnblogs.com/SeNaiTes/p/11540524.html