113

如何从日期字段中仅按月分组（而不是按天分组）？

这是我的日期字段的样子：

2012-05-01

这是我当前的 SQL：

select  Closing_Date, Category,  COUNT(Status)TotalCount from  MyTable
where Closing_Date >= '2012-02-01' and Closing_Date <= '2012-12-31'
and Defect_Status1 is not null
group by  Closing_Date, Category
4

10 回答 10

135

我会用这个：

SELECT  Closing_Date = DATEADD(MONTH, DATEDIFF(MONTH, 0, Closing_Date), 0), 
        Category,  
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY DATEADD(MONTH, DATEDIFF(MONTH, 0, Closing_Date), 0), Category;

这将在每个月的第一天分组，所以

`DATEADD(MONTH, DATEDIFF(MONTH, 0, '20130128'), 0)`

会给'20130101'。我通常更喜欢这种方法，因为它将日期保留为日期。

或者你可以使用这样的东西：

SELECT  Closing_Year = DATEPART(YEAR, Closing_Date),
        Closing_Month = DATEPART(MONTH, Closing_Date),
        Category,  
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY DATEPART(YEAR, Closing_Date), DATEPART(MONTH, Closing_Date), Category;

这真的取决于你想要的输出是什么。（在您的示例中，关闭年份不是必需的，但如果日期范围跨越年份边界，则可能是）。

于 2013-01-28T16:01:01.677 回答
46

使用DATEPART函数从日期中提取月份。

所以你会做这样的事情：

SELECT DATEPART(month, Closing_Date) AS Closing_Month, COUNT(Status) AS TotalCount
FROM t
GROUP BY DATEPART(month, Closing_Date)
于 2013-01-28T16:00:35.657 回答
19

我使用FORMAT函数来完成此操作：

select
 FORMAT(Closing_Date, 'yyyy_MM') AS Closing_Month
 , count(*) cc 
FROM
 MyTable
WHERE
 Defect_Status1 IS NOT NULL
 AND Closing_Date >= '2011-12-01'
 AND Closing_Date < '2016-07-01' 
GROUP BY FORMAT(Closing_Date, 'yyyy_MM')
ORDER BY Closing_Month
于 2016-10-05T01:55:57.300 回答
12

通过添加MONTH(date_column).GROUP BY

SELECT Closing_Date, Category,  COUNT(Status)TotalCount
FROM   MyTable
WHERE  Closing_Date >= '2012-02-01' AND Closing_Date <= '2012-12-31'
AND    Defect_Status1 IS NOT NULL
GROUP BY MONTH(Closing_Date), Category
于 2017-10-04T10:25:00.403 回答
2

尝试这个：

select min(closing_date), date_part('month',closing_date) || '-' || date_part('year',closing_date) AS month,
Category, COUNT(Status)TotalCount 
FROM MyTable
where Closing_Date >= '2012-02-01' AND Closing_Date <= '2012-12-31'
AND Defect_Status1 is not null
GROUP BY month, Category,
ORDER BY 1

这样，您将按连接的日期格式进行分组，并由 -

于 2019-11-15T14:37:35.253 回答
1

DATEPART 函数在 MySQL 5.6 上不起作用，而是使用 MONTH('2018-01-01')

于 2018-04-23T14:18:14.693 回答
0

SQL Server 2012 以上版本，

SELECT  format(Closing_Date,'yyyy-MM') as ClosingMonth,
        Category,  
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY format(Closing_Date,'yyyy-MM'), Category;
于 2020-09-15T02:47:36.167 回答
0 
SELECT  to_char(Closing_Date,'MM'), 
        Category,  
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY Category;
于 2018-11-06T08:08:03.357 回答
-1

您可以使用 Year()、Month() Day() 和 datepart() 来做到这一点。

在您的示例中，这将是：

select  Closing_Date, Category,  COUNT(Status)TotalCount from  MyTable
where Closing_Date >= '2012-02-01' and Closing_Date <= '2012-12-31' 
and Defect_Status1 is not null 
group by Year(Closing_Date), Month(Closing_Date), Category
于 2013-01-28T16:00:44.080 回答
-1

试试下面的代码

SELECT  Closing_Date = DATEADD(MONTH, DATEDIFF(MONTH, 0, Closing_Date), 0), 
        Category,  
        COUNT(Status) TotalCount 
FROM    MyTable
WHERE   Closing_Date >= '2012-02-01' 
AND     Closing_Date <= '2012-12-31'
AND     Defect_Status1 IS NOT NULL
GROUP BY DATEADD(MONTH, DATEDIFF(MONTH, 0, Closing_Date), 0), Category;
于 2018-06-27T12:33:53.277 回答