Question

我遇到与此question相同的问题。但问题是，查询只适用于MySQL而不适用于MSSQL。我试图手动转换它，但我似乎无法理解像:= [value] AS [value]一样的语法等同于

所以，我想知道是否有办法将MySQL查询转换为在MSSQL上使用它？

编辑：预期输出

输入

Company  Date       Paper  Condition
Company1 19-12-2007 PaperA Release Second Term
Company1 19-12-2007 PaperA Add Third Term
Company1 19-12-2007 PaperA Append First Term
Company2 19-12-2007 PaperA Add Third Term
Company2 19-12-2007 PaperA Append First Term
Company2 19-12-2007 PaperA Add Third Term

输出

Company  Date       Paper  Condition
Company1 19-12-2007 PaperA Release Second Term
                           Add Third Term
                           Append First Term
Company2 19-12-2007 PaperA Add Third Term
                           Append First Term
                           Add Third Term

Answer 1

在SQL 2017+中，您可以使用STRING_AGG：

SELECT Company, Date, Paper, STRING_AGG(Condition,CHAR(13)+CHAR(10)) AS Condition
FROM dbo.YourTable
GROUP BY Company, Date, Paper;

在早期的SQL版本中，使用FOR XML和STUFF来删除额外的换行符：

SELECT Company, Date, Paper
    ,STUFF((SELECT CHAR(13)+CHAR(10)+Condition FROM dbo.Example AS b
    WHERE b.Company = a.Company AND b.Date = a.Date AND b.Paper = a.Paper
    FOR XML PATH(''), TYPE).value('.','nvarchar(MAX)'),1,2,'') AS Condition
FROM dbo.YourTable AS a
GROUP BY Company, Date, Paper;

将MySQL重建为MSSQL（Microsoft Server SQL）

1 个答案: