SQL 在每一天的列中插入星期几信息，不为空

Question

这是我的 [资源表] 我正在获取我的数据：

Start Date                 Time From  Time To  Time From To    Training Room
2011-05-24 00:00:00.000    8:00       23:00    8:00 - 23:00    Room1
2011-05-25 00:00:00.000    1:00       23:00    1:00 - 23:00    Room1
2011-05-26 00:00:00.000    1:00       23:00    1:00 - 23:00    Room1
2011-05-04 00:00:00.000    20:00      23:00   20:00 - 23:00    Room2
2011-05-05 00:00:00.000    20:00      22:00   20:00 - 22:00    Room2
2011-05-20 00:00:00.000    20:00      23:00   20:00 - 23:00    Room3
2011-05-21 00:00:00.000    17:00      19:00   17:00 - 19:00    Room2

我想要填充这张表 [FACT Training]：

但是我在填充没有空值的表时遇到了问题。 由于我想向每一天的列插入数据，因此只插入特定的星期几名称：

WHERE datename(dw,[Start Date]) = 'Monday'
WHERE datename(dw,[Start Date]) = 'Tuesday'
etc...

所以我的插入看起来像这样：

但需要每天过滤...

Answer 1

查看您描述的问题，我一开始只将列值放入正确的星期几，这将创建 7 行，每行仅填充 [Start Date] 所在的那一天的列。

SELECT
    [Monday] =
        CASE WHEN DATENAME(DW,[Start Date]) = 'Monday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
    ,[Tuesday] = 
        CASE WHEN DATENAME(DW,[Start Date]) = 'Tuesday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
    ,[Wednesday] = 
        CASE WHEN DATENAME(DW,[Start Date]) = 'Wednesday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
    ,[Thursday] = 
        CASE WHEN DATENAME(DW,[Start Date]) = 'Thursday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
    ,[Friday] = 
        CASE WHEN DATENAME(DW,[Start Date]) = 'Friday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
    ,[Saturday] = 
        CASE WHEN DATENAME(DW,[Start Date]) = 'Saturday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
    ,[Sunday] = 
        CASE WHEN DATENAME(DW,[Start Date]) = 'Sunday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END
FROM
    [Resource table]

但后来我想，您可能希望将所有这些显示在一行中，在这种情况下，您需要按某个或多个值对它们进行分组。我不知道用于为组创建列值串联列表的 SQL 聚合函数，因此您可能需要创建一个，但您可以按培训室对它进行分组，如果每次培训每天只有一个条目room 可以使用类似下面的东西（SQL 纯粹主义者现在可能想把目光移开）：

SELECT
    [Week Id] = CONVERT(VARCHAR,DATEPART(YEAR,[Start Date])) + '-' + CONVERT(VARCHAR,DATEPART(WEEK,[Start Date]))
    ,[Training Room]
    ,[Monday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Monday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
    ,[Tuesday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Tuesday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
    ,[Wednesday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Wednesday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
    ,[Thursday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Thursday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
    ,[Friday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Friday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
    ,[Saturday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Saturday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
    ,[Sunday] = MAX(CASE WHEN DATENAME(DW,[Start Date]) = 'Sunday' THEN ISNULL([Training Room],'') + N' - ' + [Time From To] ELSE '' END)
FROM
    [Resource table] 
GROUP BY 
    CONVERT(VARCHAR,DATEPART(YEAR,[Start Date])) + '-' + CONVERT(VARCHAR,DATEPART(WEEK,[Start Date]))
    ,[Training Room]

您总是可以省略我分组的两个初始列（[Week Id] 和 [Training Room]）的声明，因为您不必为了查看它们而显示它们。