Group By Date and SUM int - 日期格式和顺序

Question

我正在尝试获取一天所售数量的总和。我需要将结果按日期排序。下面的查询给出了我需要的确切结果，除了日期没有格式化为我需要的格式。

SELECT  CAST(Datetime AS DATE) AS 'date', SUM(quantity) as total_quantity
FROM Invoice_Itemized ii
INNER JOIN Invoice_Totals it ON it.Invoice_Number = ii.Invoice_Number
WHERE ii.ItemNum = '4011'
AND it.datetime > '05/15/2015'
GROUP BY CAST(Datetime AS DATE)

SELECT DATENAME(MM, datetime) + ' ' + CAST(DAY(datetime) AS VARCHAR(2)) AS [DD Month], SUM(quantity) as total_quantity
FROM Invoice_Itemized ii
INNER JOIN Invoice_Totals it ON it.Invoice_Number = ii.Invoice_Number
WHERE ii.ItemNum = '4011'
AND it.datetime > '05/15/2015'
GROUP BY DATENAME(MM, datetime) + ' ' + CAST(DAY(datetime) AS VARCHAR(2))

顶部查询的结果：

1. 2015-05-15 91.43
2. 2015-05-16 84.77

底部查询的结果：

1. 6 月 1 日 128.34
2. 6 月 10 日 85.06

顶部查询按我需要的顺序为我提供了我需要的信息。 底部查询为我提供了我需要的日期格式，但顺序错误。

Answer 1

如果你真的需要应用不同的格式，你可以使用派生表：

select 
    DATENAME(MM, [date]) + ' ' + CAST(DAY([date]) AS VARCHAR(2)) AS [DD Month], 
    total_quantity 
from 
(
    SELECT  CAST([Datetime] AS DATE) AS [date], SUM(quantity) as total_quantity
    FROM Invoice_Itemized ii
    INNER JOIN Invoice_Totals it ON it.Invoice_Number = ii.Invoice_Number
    WHERE ii.ItemNum = '4011'
    AND it.[datetime] > '05/15/2015'
    GROUP BY CAST(Datetime AS DATE)
) as X

这样您可以将结果包装到派生表中，然后对其应用其余操作。

我认为这也可以，但现在无法测试：

SELECT  DATENAME(MM, CAST([datetime] AS DATE)) + ' ' 
+ CAST(DAY(CAST([datetime] AS DATE)) AS VARCHAR(2)) AS [DD Month], 
SUM(quantity) as total_quantity
FROM Invoice_Itemized ii
INNER JOIN Invoice_Totals it ON it.Invoice_Number = ii.Invoice_Number
WHERE ii.ItemNum = '4011'
AND it.[datetime] > '05/15/2015'
GROUP BY CAST([datetime] AS DATE)