• mssql sqlserver 不固定行转列数据(动态列)


    转自:http://www.maomao365.com/?p=5471
    摘要:
    下文主要讲述动态行列转换语句,列名会根据行数据的不同,
    动态的发生变化
    ----------------------------------------------------
    实现思路:
    主要将待生成的动态列名,采用脚本拼接起来,然后采用pivot函数
    运行,得到相应的结果
    本脚本运行环境:
    sql server 2008 

    /*生成源数据表*/
    create table #t
    (compname varchar(20),
    cheXi varchar(30),
    dayInfo int,
    daySaleValue int)
    
    /*生成源数据*/
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','锐志','1',20)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','皇冠','1',10)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','霸道','2',30)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','锐志','3',40)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','RAV4','4',60)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','锐志','5',8)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','霸道','6',6)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','RAV4','5',9)
    insert into #t(compname,cheXi,dayInfo,daySaleValue) values('一汽丰田','RAV4','10',10)
    
    
    
    /*
     select * from 
     (select compname,daySaleValue,dayInfo,chexi from  #t) as d
     /*注意事项: pivot所涉及的聚合列 value_column  和 pivot_column 
      都必须存在 上面的查询表中
     */
     pivot(sum(daySaleValue) for dayInfo 
       in([1],[2],[3],[4],[5],[6],[7],[8],[9],[10])) 
       t ;
    */
    /*拼接字符串*/
    declare @sql varchar(max)
    set @sql =' select * from 
     (select compname,daySaleValue,dayInfo,chexi from  #t) as d
       pivot(sum(daySaleValue) for dayInfo 
       in( 
     ';
    
    
    /*动态组合列名*/
     declare @lieMing varchar(7000)   ---定义动态生成列名存放变量
     declare @i int ,@imax int,@field varchar(60)  ---定义临时循环变量
     declare @fieldList table(keyId int identity,field varchar(60)) ---定义临时表,存放待生成动态列名的数据
     insert into @fieldList(field) select distinct dayInfo from #t  ---生成列名数据
     
     -------------循环表生成列名start--------------
     set @lieMing =''
     set @i=1 
     select @imax =max(keyId) from @fieldList t
     while @i <@imax 
     begin
        select @field =field from @fieldList t where t.keyId=@i
        if isnull(@field,'') !=''
         begin
            if @lieMing !='' begin set @lieMing =@lieMing +',' end
            set @lieMing = @lieMing+'['+@field+']';
         end
        set @i=@i+1
     end
      -------------循环表生成列名end--------------
    /*动态组合列*/
    
    set @sql =@sql +@lieMing +' ))  t ;';    ---拼接sql语句
    exec (@sql)                              ---执行sql脚本,生成相关数据
        
    truncate table #t 
    drop table #t 

     

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  • 原文地址:https://www.cnblogs.com/lairui1232000/p/10430189.html
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