动态SQL语句根据数据库列来查询数据，动态的生成列名称

set ANSI_NULLS ON

set QUOTED_IDENTIFIER ON

go







/******************************************************************************************

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存储过程名称：  [contract_station_elec]

实现功能：    基准站月用电量统计报表

作者：      巫航



----------------------------------------------------------------------------------------

修改时间    版本号    修改人  修改摘要

2013年4月26日    V3.0    巫航    创建该存储过程，由于辽宁电信的需求，需要按各用电量电流值current_size来分割大小

----------------------------------------------------------------------------------------

******************************************************************************************/

alter PROCEDURE [dbo].[rpt_contract_station_elec]

  @station varchar(8000) = '',

  @time    varchar(8000) = '',

  @time_start datetime = null,

  @time_end   datetime = null,

  @sort       varchar(8000) = ''

as

begin

    set nocount on;



    declare @nv_table_name nvarchar(max); --表名称变量

    declare @nv_sql nvarchar(max);        --动态sql变量

    declare @v_station_kind int;

    declare @v_name varchar(30);

    declare @nv_column_name nvarchar(max);--SUM+列名称

    DECLARE @table VARCHAR(8000)

    DECLARE @sql nvarchar(max);

    

    SET @table = 'his_powermonth_' +

        CONVERT(VARCHAR(8000), DATEPART(yy, @time_start))

    --如果表不存在，使用没有数据的原始表

    IF NOT EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[' + @table + ']') AND type in (N'U'))

    BEGIN

        set @table = 'his_powermonth'

    END

    --创建临时表,放置局站

    DECLARE @station_where VARCHAR(8000)

    SET @station_where = ''

    IF @station<>''

    BEGIN

        IF object_id('tempdb..#TEMPTB1') is not null

            drop table #TEMPTB1

        CREATE table #TEMPTB1

        (

            station_sn VARCHAR(64)

        )

        CREATE clustered index #TEMPTB1_Index1 on #TEMPTB1 (station_sn)

        SET @sql = 'INSERT INTO #TEMPTB1 ' + @station

        EXEC(@sql)

        SET @station_where = 'INNER JOIN #TEMPTB1 tmp ON t.station_sn = tmp.station_sn'

    END

    



    --删除可能存在的临时表

    if object_id('tempdb..#temp_a') is not null

    begin

      drop table #temp_a;

    end

    --建立遥测量临时表

    CREATE TABLE #temp_a(

        [station_sn] varchar(64) not null,

        [current_size] tinyint,

        [value] real

    );

    SET @sql = 'INSERT INTO #temp_a([station_sn],[current_size],[value]) 

    select t.[station_sn],t.[current_size],sum(t.[value]) as [value] 

    FROM '+@table+' t ' + @station_where +' group by t.[current_size],t.[station_sn]'

    

    exec(@sql);

--    select * from #temp_a;

--    insert into #temp_a([station_sn],[am_kind],[value]) SELECT [station_sn],[am_kind],sum([value]) as [value] FROM [ems_his].[dbo].[his_powermonth_2013] 

--group by [am_kind],station_sn



    --删除可能存在的临时表

    if object_id('tempdb..#temp_table') is not null

    begin

      drop table #temp_table;

    end

    --建立电流值大小临时表

    CREATE TABLE #temp_table(

      [current_size] int not null

    );



    set @nv_table_name = ' a.*';

    set @nv_column_name = '';



    declare cs1 cursor for

    select [name] from [ems_cfg].[dbo].[cfg_currentsize]

    open cs1

    fetch next from cs1 into @v_name

    while @@fetch_status = 0

        begin

        set @nv_table_name = @nv_table_name + ' ,b.[' +@v_name+']*a.value as ['+@v_name +']';

        set @nv_column_name = @nv_column_name + ' ,ROUND(SUM(['+@v_name+']),2) as ['+@v_name+']'

        select @nv_sql = 'alter table #temp_table add [' + @v_name + '] int default 0';

        --print(@nv_sql);

        exec(@nv_sql);

        fetch next from cs1 into @v_name;

        end

    close cs1

    deallocate cs1



    insert into #temp_table(current_size)

    select current_size from [ems_cfg].[dbo].[cfg_currentsize]



    declare cs2 cursor for

    select [current_size],[name] from [ems_cfg].[dbo].[cfg_currentsize]

    open cs2

    fetch next from cs2 into @v_station_kind,@v_name

    while @@fetch_status = 0

    begin

        select @nv_sql = 'update #temp_table set [' + @v_name + '] = 1

         where [current_size] = ' + rtrim(@v_station_kind);

        print(@nv_sql);

        exec(@nv_sql);

        fetch next from cs2 into @v_station_kind,@v_name;

    end

    close cs2

    deallocate cs2



--  select [am_kind] from [ems_cfg].[dbo].[cfg_amkind];

--  select * from #temp_table;



    set @nv_table_name ='select s.station_name,l.lsc_name,p.precinct_name,'+ @nv_table_name + 

        ' from #temp_a a 

        left join #temp_table b on a.[current_size] = b.[current_size]

        left join ems_cfg.dbo.cfg_station s on s.station_sn=a.station_sn

        left join ems_cfg.dbo.cfg_lsc l on l.lsc_id=s.lsc_id

        left join ems_cfg.dbo.cfg_precinct p on p.lsc_id=l.lsc_id and p.precinct_id=s.precinct_id';

    set @nv_sql = 'select station_name,lsc_name,precinct_name'+@nv_column_name+' from ('+@nv_table_name+') t 

            group by station_name,lsc_name,precinct_name'

    print(@nv_sql);

    exec(@nv_sql);

    

    --查询出第二个表

    SELECT [current_size],[name] FROM [ems_cfg].[dbo].[cfg_currentsize]

end

经常遇到用户需要动态的查询每一列的统计数据，烦都烦死了，请教了DBA，帮忙花了点时间写了这个动态SQL，根据配置表的ID号，名称来动态生成数据表格和数据集

WEB上再根据名称来生成对应的中文列头