SQL SERVER：子查询中的 WHERE 子句从外部查询中获取属性答案

【问题标题】：SQL SERVER: WHERE clause in subquery to get attribute from outer querySQL SERVER：子查询中的 WHERE 子句从外部查询中获取属性
【发布时间】：2020-04-10 23:00:37
【问题描述】：

所以这里是查询

SELECT TOP 10 * FROM
(SELECT
    Country_Region AS CR,
    WeekOfYear,

    (SELECT SumConfWeekly FROM
    (
        SELECT Country_Region, SUM(ConfirmedWeekly) AS SumConfWeekly
        FROM covid_19_aggr
        GROUP BY CUBE (Country_Region)
    ) AS C
    WHERE C.Country_Region=T1.CR) AS SC2,
    ConfirmedWeekly
FROM 
    covid_19_aggr
)
AS T1
PIVOT(
    SUM(ConfirmedWeekly)
    FOR WeekOfYear IN ([4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14])
) AS PT1
ORDER BY SC2 DESC;

问题出在 where 子句中，我想将 Country_Region 从子查询匹配到外部查询。如何解决这个问题？任何帮助将不胜感激。

【问题讨论】：

标签： sql-server subquery where-clause

【解决方案1】：

尝试以下方法：

SELECT TOP 10 * FROM
(
    SELECT
        Country_Region AS CR,
        WeekOfYear,
        (
            SELECT SumConfWeekly FROM
                (
                    SELECT Country_Region, SUM(ConfirmedWeekly) AS SumConfWeekly
                    FROM @covid_19_aggr
                    GROUP BY CUBE (Country_Region)
                ) AS C
            WHERE C.Country_Region=T2.Country_Region
        ) AS SC2,
        ConfirmedWeekly
    FROM 
        @covid_19_aggr T2
)
AS T1
PIVOT
(
    SUM(ConfirmedWeekly)
    FOR WeekOfYear IN ([4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14])
) AS PT1
ORDER BY SC2 DESC;

【讨论】：

@Tathagata 有时以更好的方式格式化代码会有所帮助。啊！
这是我第一次参加数据库课程，我是菜鸟;-;
@Tathagata 你在做 gr8，你可以使用this 来格式化代码。