性能优化：SQL Server 性能调优之查询从20秒至2秒的优化方法

select *from(
select *,ROW_NUMBER() OVER (ORDER BY sc desc) as rank
from(
select *,
case when ( 40-(a.p*(case when a.p > 0 then 1 else -0.5 end)))<=30
then 30
else ( 40-(a.p*(case when a.p > 0 then 1 else -0.5 end)))
end as sc
from (
select * from (
select a.ProjectNumber, a.ProjectName, a.BaojianNumber, a.BaojianName, a.ToubiaoPerson,
sum(UnitPrice) as sumPrice,
b.price as avgPrice,
((sum(UnitPrice)-b.price)/nullif(b.price,0)*100) as p,
sum(case when UnitPrice>b.price then b.price else UnitPrice end )as pprice,
sum(case when UnitPrice>MaxPrice then 1 else 0 end ) as countChao
from ToubiaoDetailTest1 a
join (
select ProjectNumber, ProjectName, BaojianNumber, BaojianName, avg(price) as price
from(
select * from(
select ProjectNumber, ProjectName, BaojianNumber, BaojianName, ToubiaoPerson,
SUM(UnitPrice) as price,
SUM(case when UnitPrice>MaxPrice then 1 else 0 end ) as countChao
from ToubiaoDetailTest1
group BY ProjectNumber, ProjectName, BaojianNumber, BaojianName, ToubiaoPerson
) tt
where tt.countChao = 0
) t
group by ProjectNumber, ProjectName, BaojianNumber, BaojianName
) b
on a.ProjectNumber=b.ProjectNumber and a.ProjectName=b.ProjectName and a.BaojianNumber=b.BaojianNumber and a.BaojianName=b.BaojianName
group by a.BaojianNumber, a.BaojianName, a.ProjectNumber, a.ProjectName, a.ToubiaoPerson, b.price
) tt
where tt.countChao=0
) a
) b
) t
order by rank