[易飞]EXP(SUM(LOG(字段)))的实践

在写到一半代码的时候，需要统计指定行的乘积。想到SQL中有
EXP(SUM(LOG(字段)))的新函数试试。完全代码如下

-- =============================================   
-- Author: <David Gong>   
-- Create date: <2015-9-11>   
-- Description: <统计COB品质状况表>    
-- ============================================= 
ALTER Proc UP_Proc_COB
(
    @year  as char(4)
)
as
begin

create table #tmpCOB( 
    项目 varchar(20),
    月份 varchar(20),
    百分比 decimal(8,4) default (0)
);

--declare @year as char(4)
--set @year=‘2015‘
declare @yearmonth as char(6)
declare @i int

set @i=1
declare @month char(2)
while @i<=12

BEGIN
   set @month=right(@i+100,2) 
   set @yearmonth =@year+right(@i+100,2) 

   if(@yearmonth<=CONVERT(char(6),getdate(),112))
   begin

       --统计当月绑定合格率
        insert into #tmpCOB(项目,月份,百分比)
        select ‘1.绑定合格率‘ as 项目, @month 月份, cast(round(sum(测试数量-不良数量)*1.0/sum(测试数量),4) as  numeric(8,4)) 合格率 
        from 制程COB绑测
        where CONVERT(char(6),日期,112)=@yearmonth

         --统计当月外观合格率
        insert into #tmpCOB(项目,月份,百分比)
        select ‘2.外观合格率‘ as 项目, @month 月份, cast(round(sum(测试数量-不良数量)*1.0/sum(测试数量),4) as  numeric(8,4)) 合格率 
        from 制程COB外观
        where CONVERT(char(6),日期,112)=@yearmonth

        --统计成测合格率
        insert into #tmpCOB(项目,月份,百分比)
        select ‘3.终测合格率‘ as 项目, @month 月份, cast(round(sum(测试数量-不良数量)*1.0/sum(测试数量),4) as  numeric(8,4)) 合格率 
        from 制程COB成测
        where CONVERT(char(6),日期,112)=@yearmonth

        --统计FQC合格率
        insert into #tmpCOB(项目,月份,百分比)
        select ‘4.FQC合格率‘ as 项目, @month 月份, cast(round(sum(检验数量-不合格数量)*1.0/sum(检验数量),4) as  numeric(8,4)) 合格率 
        from 制程FQC_COB_检验
        where CONVERT(char(6),检验日期,112)=@yearmonth


    end
   set @i=@i+1


END


select * into #COB
from #tmpCOB pivot(max(百分比) for 月份 in ([01],[02],[03],[04],[05],[06],[07],[08],[09],[10],[11],[12])) a


select 项目,[01] 一月,[02] 二月,[03] 三月,[04] 四月,[05] 五月,[06] 六月,[07] 七月,[08] 八月,[09] 九月,[10] 十月,[11] 十一月,[12] 十二月
FROM #COB 
union all
---处理指定行的列乘积计算
/*
--方法一: CASE WHEN 行转列 之后PIVOT函数指定列
select * 
from (select  ‘6.制程一次通过率‘ as 项目,月份,ROUND(sum(绑定百分比)*sum(外观百分比)*sum(终测百分比),4) as 百分比 from(
select 项目,月份,
CASE WHEN 项目=‘1.绑定合格率‘ then 百分比 else 0 end 绑定百分比 ,
CASE WHEN 项目=‘2.外观合格率‘ then 百分比 else 0 end 外观百分比 , 
CASE WHEN 项目=‘3.终测合格率‘ then 百分比 else 0 end 终测百分比
from #tmpCOB
where  项目<>‘4.FQC合格率‘ )
A
group by A.月份) as c pivot(max(百分比) for 月份 in ([01],[02],[03],[04],[05],[06],[07],[08],[09],[10],[11],[12])) b
*/


--方法二 直接采用EXP(SUM(LOG(字段)))
SELECT ‘6.制程一次通过率‘,
ROUND(EXP(SUM(LOG([01]))),4) as 一月,
ROUND(EXP(SUM(LOG([02]))),4) as 二月,
ROUND(EXP(SUM(LOG([03]))),4) as 三月, 
ROUND(EXP(SUM(LOG([04]))),4) as 四月,
ROUND(EXP(SUM(LOG([05]))),4) as 五月,
ROUND(EXP(SUM(LOG([06]))),4) as 六月,
ROUND(EXP(SUM(LOG([07]))),4) as 七月,
ROUND(EXP(SUM(LOG([08]))),4) as 八月,
ROUND(EXP(SUM(LOG([09]))),4) as 九月,
ROUND(EXP(SUM(LOG([10]))),4) as 十月,
ROUND(EXP(SUM(LOG([11]))),4) as 十一月,
ROUND(EXP(SUM(LOG([12]))),4) as 十二月
FROM #COB 
where 项目<>‘4.FQC合格率‘
union all

select case when 项目=‘FQC合格率目标‘ then ‘5.FQC合格率目标‘ else ‘7.一次直通率目标‘ end as 项目,
一月,二月,三月,四月,五月,六月,七月 ,八月 ,九月 ,十月,十一月,十二月 from 制程FQC目标
where 系列=‘COB‘ and 年份=@year

drop table #tmpCOB
drop table #COB
end

效果