除了添加索引   我加了索引反而变慢了呢  添加索引数据还容易不准确

;with AA as (

select * from (

select *,ROW_NUMBER() over(partition by product_code  order by s_date desc ) t1,replace(replace(replace(convert(varchar,s_date,102

),'-',''),':',''),' ','') as 开始时间,replace(replace(replace(convert(varchar,e_date,102

),'-',''),':',''),' ','') as 结束时间

from DW_XGTB  where brand in ('芭欧/BOOL','芭欧','薇薇卡','薇薇卡/VIVICA&CO.','VY','薇娅（VIYA）','薇娅')

) t2 where t2.t1<=4 and platform is not null),

BB AS (

select DesignKCode,ExtStr1,BM ,PP

from DW_BoolProductsFile 

),

CC as (

SELECT  BB.DESIGNKCODE,AA.product_code,AA.brand,(CAST(开始时间 as varchar(20))+'-'+CAST(结束时间 as varchar(20))) 活动时间,result_Y,AA. platform,AA.shop_name

from AA

 left join BB

 ON  AA.brand=BB.PP and

 AA.product_code=BB.BM or AA.product_code=BB.EXTSTR1 

 ),

DD AS (

 select DISTINCT * from CC where DesignKCode is not null)

 select * from (

 select * ,row_number() over(partition by designkcode order by DD.活动时间  desc) r

 from DD) DD where DD.r<=4