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  • SQL ROW_NUMBER() OVER函数的基本用法用法

    语法:

    ROW_NUMBER() OVER(PARTITION BY GroupingColumnName ORDER BY WithinGroupOrderbyColumnName)

    按GroupingColumnName分组后,在组内按照指定(或默认)的排序规则生成行号。

    e.g

    SELECT * FROM GreekGod

    ID          FullName             Gender
    ----------- -------------------- ----------
    1           Apollo               MALE
    2           Hera                 FEMALE
    3           Zeus                 MALE
    4           Venus                FEMALE

    SELECT *,ROW_NUMBER() OVER(PARTITION BY Gender ORDER BY FullName DESC) ROWNUM FROM GreekGod

    ID          FullName             Gender     ROWNUM
    ----------- -------------------- ---------- --------------------
    4           Venus                FEMALE     1
    2           Hera                 FEMALE     2
    3           Zeus                 MALE       1
    1           Apollo               MALE       2

    SELECT * FROM
    (SELECT *,ROW_NUMBER() OVER(PARTITION BY Gender ORDER BY FullName DESC) ROWNUM FROM GreekGod) TResult
    WHERE ROWNUM=1

    ID          FullName             Gender     ROWNUM
    ----------- -------------------- ---------- --------------------
    4           Venus                FEMALE     1
    3           Zeus                 MALE       1


    
    
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  • 原文地址:https://www.cnblogs.com/wsion/p/4208775.html
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