表是个流水的记录，假设每5秒记录一次当前的温度 ，如下：
TimePoint TempValue PF
20131201080100 20.02 0.2
20131201080105 27.33 1.2
20131201080110 31.36 1.4
20131201080115 32.00 1.8
20131201080120 28.59 0.2
20131201080125 50.26 1.4
20131201080130 20.34 1.6
20131201080135 40.18 1.5
20131201080140 35.00 1.0
20131201080145 20.21 0.2
20131201080150 20.54 0.2
20131201080155 31.22 0.9
得到数据
20131201080100 20.02 关
20131201080110 31.36 开
20131201080120 28.59 关
20131201080135 40.18 开
20131201080145 20.21 关
中间隔多少条记录不一定，就是要看那个临界的记录，根据 后面两个列进行判断，
TempValue 在 30.00-50.00 之间 并且 PF 在 1.0-2.0之间
这种查询，因个人水平问题，除了循环判断，没有太好的想法，求大神指点。
附上测试代码
with tb(TimePoint,TempValue,PF)as(
select 20131201080100,20.02,0.2 union
select 20131201080105,27.33,1.2 union
select 20131201080110,31.36,1.4 union
select 20131201080115,32.00,1.8 union
select 20131201080120,28.59,0.2 union
select 20131201080125,50.26,1.4 union
select 20131201080130,20.34,1.6 union
select 20131201080135,40.18,1.5 union
select 20131201080140,35.00,1.0 union
select 20131201080145,20.21,0.2 union
select 20131201080150,20.54,0.2 union
select 20131201080155,31.22,0.9 )
select * from tb
------解决方案--------------------
if object_id('tempdb..#a') is not null drop table #a
create table #a (TimePoint varchar(50),TempValue float,PF float)
insert into #a
select 20131201080100,20.02,0.2 union
select 20131201080105,27.33,1.2 union
select 20131201080110,31.36,1.4 union
select 20131201080115,32.00,1.8 union
select 20131201080120,28.59,0.2 union
select 20131201080125,50.26,1.4 union
select 20131201080130,20.34,1.6 union
select 20131201080135,40.18,1.5 union
select 20131201080140,35.00,1.0 union
select 20131201080145,20.21,0.2 union
select 20131201080150,20.54,0.2 union
select 20131201080155,31.22,0.9
-- select * from #a
---开始查询
;with cte as(
select * , row_number() over (order by getdate()) num,
ison=(case when TempValue between 30.00 and 50.00 and PF between 1.0 and 2.0 then 2 else 1 end)
from #a)
select TimePoint,TempValue,ison=case when ison=1 then '关' else '开' end from cte a where
not exists(select 1 from cte where num=a.num-1 and ison=a.ison)
----查询结果
TimePoint TempValue ison
-------------------------------------------------- ---------------------- ----
20131201080100 20.02 关