请教一条sql语句的优化

declare @c_id  intSEt @c_id =19select  top 10000 *  into #temp from [CarVehicleData_tbl] where [email protected]_id order by [CSN_UpdateTime] descselect max([CSN_ID]) as [CSN_ID],  c_id, [CSN_Part],[CSN_Type], max([CSN_UpdateTime]) as [CSN_UpdateTime] into #temp2from #tempgroup by c_id ,[CSN_Part],[CSN_Type]select *,(select top 1 [CSN_DataOriginal]  from [CarVehicleData_tbl] a where b.csn_updateTime=a.csn_updateTime order by csn_updateTime desc ) as [CSN_DataOriginal] into  #temp3 from #temp2  bselect c_id,[CSN_Part],data1 =max( case csn_type when 0 then [CSN_DataOriginal] end ),data2=max( case csn_type when 1 then [CSN_DataOriginal] end ) into #temp4 from #temp3group by c_id,[CSN_Part]select *,null as a ,null as b from #temp3drop table  #tempdrop table  #temp2drop table  #temp3drop table  #temp4

declare @c_id  intSEt @c_id =19select  top 10000 *  into #temp from [CarVehicleData_tbl] where [email protected]_id order by [CSN_UpdateTime] DESCCREATE INDEX IX_#temp_ALL ON #temp(c_id,[CSN_Part],csn_type,csn_updateTime,CSN_DataOriginal) INCLUDE ([CSN_DataOriginal])select    a.c_id,     a.[CSN_Part],     data1=MAX(CASE WHEN a.[CSN_Type]=0 THEN b.csn_updateTime IS NOT NULL THEN a.CSN_DataOriginal end),    data2=MAX(CASE WHEN a.[CSN_Type]=1 THEN b.csn_updateTime IS NOT NULL THEN a.CSN_DataOriginal end