SQL按月和年分组

我不确定在下面的SQL查询中应该写些什么来显示“日期”列，例如：“ month-year”-“ 9-2011”。

SELECT MONTH(date) + '.' + YEAR(date) AS Mjesec, SUM(marketingExpense) AS SumaMarketing, SUM(revenue) AS SumaZarada 
FROM [Order]
WHERE (idCustomer = 1) AND (date BETWEEN '2001-11-3' AND '2011-11-3')
GROUP BY MONTH(date), YEAR(date)

因此，我要做的是将第一列中的数据更改为显示月份和年份，而不是仅显示月份。

SELECT CAST(MONTH(date) AS VARCHAR(2)) + '-' + CAST(YEAR(date) AS VARCHAR(4)) AS Mjesec, SUM(marketingExpense) AS SumaMarketing, SUM(revenue) AS SumaZarada 
FROM [Order]
WHERE (idCustomer = 1) AND (date BETWEEN '2001-11-3' AND '2011-11-3')
GROUP BY CAST(MONTH(date) AS VARCHAR(2)) + '-' + CAST(YEAR(date) AS VARCHAR(4))

或者如@ 40-Love所述，您可以使用前导零进行转换：

GROUP BY 
  CAST(YEAR(date) AS VARCHAR(4)) + '-' + right('00' + CAST(MONTH(date) AS VARCHAR(2)), 2) 

我想是MS SQL，因为它看起来像MS SQL语法。

因此，您应该在分组行中输入与select ex中相同的内容：

Select MONTH(date)+'-'+YEAR(date), ....
...
...
...
group by MONTH(date)+'-'+YEAR(date)

如果我理解正确。为了按要求对结果进行分组，Group By子句需要与select语句具有相同的表达式。

GROUP BY MONTH(date) + '.' + YEAR(date)

要将日期显示为“月日期”格式，请更改“。”。到'-'的完整语法将是这样的。

SELECT MONTH(date) + '-' + YEAR(date) AS Mjesec, SUM(marketingExpense) AS
SumaMarketing, SUM(revenue) AS SumaZarada 
FROM [Order]
WHERE (idCustomer = 1) AND (date BETWEEN '2001-11-3' AND '2011-11-3')
GROUP BY MONTH(date) + '.' + YEAR(date)

在上面的SQL Server 2012中，我更喜欢使用format（）函数，更加简化。

SELECT format(date,'MM.yyyy') AS Mjesec, SUM(marketingExpense) AS SumaMarketing, SUM(revenue) AS SumaZarada 
FROM [Order]
WHERE (idCustomer = 1) AND (date BETWEEN '2001-11-3' AND '2011-11-3')
GROUP BY format(date,'MM.yyyy')

您可以尝试乘以调整年份和月份，以便它们成为一个数字。根据我的测试，它的运行速度比快得多format(date,'yyyy.MM')。我更喜欢将前一年用于分类目的。从MS SQL Server Express版本12.0创建的代码。

SELECT (YEAR(Date) * 100) + MONTH(Date) AS yyyyMM
FROM [Order]
...
GROUP BY (YEAR(Date) * 100) + MONTH(Date)
ORDER BY yyyyMM

Yet another alternative: 

Select FORMAT(date,'MM.yy')
...
...
group by FORMAT(date,'MM.yy')

在postgresql中，我可以使用日期格式函数（to_char）编写类似的查询，并仅按日期进行分组：

SELECT to_char (datum, 'MM-YYYY') AS mjesec 
FROM test 
GROUP BY datum 
ORDER BY datum;

SQL Server当然也可以实现这种功能，不是吗？

对于mariaDB，您可以：

SELECT DATE_FORMAT(date, '%m-%Y')
FROM [Order]
GROUP BY 
DATE_FORMAT(date, '%m-%Y')

链接：https：//mariadb.com/kb/zh/library/date_format/

如果要保留日期时间数据类型的字段，请尝试使用以下方法：

SELECT DATEADD(MONTH, DATEDIFF(MONTH, 0, o.[date]), 0) AS Mjesec, SUM(marketingExpense) AS SumaMarketing, SUM(revenue) AS SumaZarada 
FROM [Order] o
WHERE (idCustomer = 1) AND (o.[date] BETWEEN '2001-11-3' AND '2011-11-3')
GROUP BY DATEADD(MONTH, DATEDIFF(MONTH, 0, o.[date]), 0)

也可以轻松地按小时，天，周，年分组。
我希望对某人有用，

问候！