--> 测试数据：[test]
if object_id('[test]') is not null drop table [test]
create table [test](
[ID] int,
[时间] varchar(5),
[压力] int,
[温度] int,
[湿度] int
)
insert [test]
select 1,'time1',10,15,20 union all
select 2,'time2',11,16,21 union all
select 3,'time3',12,17,22 union all
select 4,'time4',13,18,23 union all
select 5,'time5',14,19,24

update test
set [压力]=t.[压力] from(
select px=ROW_NUMBER()over(order by getdate()),
[压力] from test where [时间] in('time4','time5')
)t
where test.ID=t.px

select * from test
/*
ID    时间    压力    温度    湿度
1    time1    13    15    20
2    time2    14    16    21
3    time3    12    17    22
4    time4    13    18    23
5    time5    14    19    24
*/

说实话，你给的这个测试数据的时间字段让人很蛋疼