Question

SELECT
    SUM(`PR Requests`),
    CAR,
    Request_State
FROM
    (
        SELECT DISTINCT
            Po_Line_Amount AS `PR Requests`,
            Project_Code AS CAR,
            Request_State
        FROM
            Table1
        WHERE NOT (
            Request_State LIKE '%canceled%'
            OR Request_State LIKE '%pulled_back%'
        )
    ) t

该查询有效并返回正确总结的不同金额。我尝试在更大的查询中解决这些问题：

SELECT ID, Title, `Start Date`, `7ca. CAR` AS CAR, b.PR, c.Capex, c.PO_Committed AS `PO Committed`, c.PO_Invoiced AS `PO Invoiced`
FROM Table3 a
LEFT JOIN (
    SELECT
    SUM(`PR Requests`) AS PR,
    CAR,
    Request_State
FROM
    (
        SELECT DISTINCT
            Po_Line_Amount AS `PR Requests`,
            Project_Code AS CAR,
            Request_State
        FROM
            Table1
        WHERE NOT (
            Request_State LIKE '%canceled%'
            OR Request_State LIKE '%pulled_back%'
        )
    ) t
) b ON b.CAR = a.`7ca. CAR`
LEFT JOIN (
    SELECT Car_Number, SUM(Capex) AS Capex, SUM(PO_Committed) AS PO_Committed, SUM(PO_Invoiced) AS PO_Invoiced
    FROM Table2
    GROUP BY Car_Number
) c ON c.Car_Number = a.`7ca. CAR`
WHERE `Snapshot` = (SELECT MAX(`Snapshot`) FROM RandD_Playbook)
AND NOT ISNULL(PO_Committed)
GROUP BY
    ID, Title

这样运行，但它给了我NULL的PR，我期望获得PR请求的SUM。我错了吗？

Answer 1

如果PR为NULL，并且由于您正在进行LEFT JOIN，这只能表示b.CAR = a.7ca. CAR

条件下没有结果

Answer 2

弄清楚了;我突然想到在SELECT DISTINCT代码的t之后添加一个组。

SELECT ID, Title, `Start Date`, `7ca. CAR` AS CAR, b.PR, c.Capex, c.PO_Committed AS `PO Committed`, c.PO_Invoiced AS `PO Invoiced`
FROM Table3 a
LEFT JOIN (
    SELECT
    SUM(`PR Requests`) AS PR,
    CAR,
    Request_State
FROM
    (
        SELECT DISTINCT
            Po_Line_Amount AS `PR Requests`,
            Project_Code AS CAR,
            Request_State
        FROM
            Table1
        WHERE NOT (
            Request_State LIKE '%canceled%'
            OR Request_State LIKE '%pulled_back%'
        )
    ) t
  GROUP BY CAR
) b ON b.CAR = a.`7ca. CAR`
LEFT JOIN (
    SELECT Car_Number, SUM(Capex) AS Capex, SUM(PO_Committed) AS PO_Committed, SUM(PO_Invoiced) AS PO_Invoiced
    FROM Table2
    GROUP BY Car_Number
) c ON c.Car_Number = a.`7ca. CAR`
WHERE `Snapshot` = (SELECT MAX(`Snapshot`) FROM RandD_Playbook)
AND NOT ISNULL(PO_Committed)
GROUP BY
    ID, Title

清除了NULL。不知道为什么那里需要它，但它适用于所有情况，所以对我来说没问题。

如何总结MySQL中的不同选择

2 个答案: