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  • MSSQL列记录合并

    创建表及插入数据

    If OBJECT_ID(N'Demo') Is Not Null
        Begin
            Drop Table Demo
        End
    Else
        Begin
            Create Table Demo(
            Area nvarchar(30),
            Name nvarchar(20))
    
            Insert Into Demo(Area,Name)
            Values(N'北京',N'张三'),
            (N'上海',N'李四'),
            (N'深圳',N'王五'),
            (N'深圳',N'钱六'),
            (N'北京',N'赵七'),
            (N'北京','Tom'),
            (N'上海','Amy'),
            (N'北京','Joe'),
            (N'深圳','Leo')
        End
    Go
    SELECT ','+Name FROM dbo.Demo FOR XML PATH('')
    
    Declare @NameCollection nvarchar(500)
    Select @NameCollection=ISNULL(@NameCollection+',','')+Name From dbo.Demo
    Select @NameCollection as NameCollection

    SELECT  Area,
    (SELECT ','+Name FROM dbo.Demo WHERE Area = t.Area FOR XML PATH(''))
    AS NameCollection FROM dbo.Demo AS t
    
    SELECT Area,
    STUFF((SELECT ','+Name FROM dbo.Demo WHERE Area = t.Area FOR XML PATH('')),1,1,'')
    AS NameCollection FROM dbo.Demo AS t

    建一个函数,传入一个Area参数,根据Area来进行合并,返回合并值

    CREATE FUNCTION MergeByColumn 
    (
        -- Add the parameters for the function here
        @Area nvarchar(30)
    )
    RETURNS nvarchar(500)
    AS
    BEGIN
        -- Declare the return variable here
        DECLARE @NC nvarchar(500)  
    
        -- Add the T-SQL statements to compute the return value here
        SELECT @NC=ISNULL(@NC+',','')+Name FROM dbo.Demo WHERE Area=@Area
    
        -- Return the result of the function
        RETURN @NC
    
    END
    GO
    SELECT DISTINCT Area,dbo.MergeByColumn(Area) AS NameCollection From dbo.Demo
    
    SELECT Area,dbo.MergeByColumn(Area) AS NameCollection From dbo.Demo GROUP BY Area

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  • 原文地址:https://www.cnblogs.com/Snowfun/p/5053002.html
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