对具有空值和不同值的行进行分组

Question

我正在尝试对最后一列 (LeaveDays) 求和，并需要通过对所有列进行分组来在一行中输出，但我无法在此处对行进行分组，并获得相同的未分组结果。谢谢！

我需要输出为：

YEAR   MONTHID   MONTH   C10 C11 C12 C13 C14 C15 C16 C17 C18 C19 C20 C21 C22 LEAVEDAYS

2020     6        JUNE    P   P   P   P   H   P   P   P   P   A   P   H   A    4

Answer 1

按年和月聚合，如果给定列没有非 NULL 值，则使用 COALESCE 显示 P：

SELECT
    YEAR,
    MONTHID,
    MONTH,
    COALESCE(MAX(C10), 'P') AS C10,
    COALESCE(MAX(C11), 'P') AS C11,
    ...,
    COALESCE(MAX(C22), 'P') AS C22,
    SUM(LEAVEDAYS) AS LEAVEDAYS
FROM yourTable
GROUP BY
    YEAR,
    MONTHID,
    MONTH;

Answer 2

如果在 C10 到 C22 中找到除 P 之外的其他字符，则您将该其他字符带入结果。

我认为您可以将 max 与 keep 子句一起使用，如下所示：

SELECT
    YEAR, MONTHID, MONTH,
    MAX(C10) KEEP(DENSE_RANK LAST ORDER BY CASE WHEN C10='P' THEN 1 ELSE 2 END) AS C10,
    ...,
    MAX(C22) KEEP(DENSE_RANK LAST ORDER BY CASE WHEN C22='P' THEN 1 ELSE 2 END) AS C22,
    SUM(LEAVEDAYS) AS LEAVEDAYS
FROM your_table
GROUP BY
    YEAR, MONTHID, MONTH;

或者您可以使用如下条件聚合：

SELECT
    YEAR, MONTHID, MONTH,
    COALESCE(MAX(CASE WHEN C10<>'P' THEN C10 END),'P') AS C10,
    ...,
    COALESCE(MAX(CASE WHEN C22<>'P' THEN C22 END),'P') AS C22,
    SUM(LEAVEDAYS) AS LEAVEDAYS
FROM your_table
GROUP BY
    YEAR, MONTHID, MONTH;

Answer 3

我理解的逻辑是您只需要每列中的最小值：

SELECT YEAR, MONTHID, MONTH,
       MIN(C10) AS C10,
       ...,
       MIN(C22) AS C22,
       SUM(LEAVEDAYS) AS LEAVEDAYS
FROM t
GROUP BY YEAR, MONTHID, MONTH;

对具有空值和不同值的行进行分组

Group rows having null value and a distinct value

sql

oracle

oracle12c