sql - TSql 按日期求和

Question

我试过看一些例子，但没有一个与我想要做的事情真正相关。在我的表中，我有一列包含日期，我想做的是按日期将记录相加。例如添加 3 月 12 日、13 日、14 日等的所有记录。所以每一天都应该有它的日期和一个计数的总和。我将如何应用它？

SELECT DTTM
FROM 
[Audits].[dbo].[Miscount]
Group by DTTM
Order by DTTM desc

干杯!

Answer 1

如果您想要每天的每条记录数：

SELECT DTTM,COUNT(*) AS Total
FROM 
[Audits].[dbo].[Miscount]
Group by DTTM
Order by DTTM desc

或者，如果您想要每条记录上的字段总和：

SELECT DTTM,SUM(field1) AS Sum
FROM 
[Audits].[dbo].[Miscount]
Group by DTTM
Order by DTTM desc

或者，如果 DTTM 是日期时间，那么您可以使用：

SELECT DATEADD(dd, 0, DATEDIFF(dd, 0, DTTM)) AS DTTM,COUNT(*) AS Total
FROM 
[Audits].[dbo].[Miscount]
Group by DATEADD(dd, 0, DATEDIFF(dd, 0, DTTM))
Order by DATEADD(dd, 0, DATEDIFF(dd, 0, DTTM)) desc

较新版本的 SQL Sever 将支持 Date 类型，因此您可以这样做：

SELECT CAST(DTTM AS Date) AS DTTM,COUNT(*) AS Total
FROM 
[Audits].[dbo].[Miscount]
Group by CAST(DTTM AS Date)
Order by CAST(DTTM AS Date) desc

Answer 2

如果DTTM是一个DateTime类型那么

SELECT
            CAST([DTTM] AS Date) [Date],
            COUNT(*) [Total]
    FROM 
            [Audits].[dbo].[Miscount]
    GROUP BY
            CAST([DTTM] AS Date)
    ORDER BY
            1 DESC

会做。这里有一些小提琴来演示。