Question

这是我的表：

Site_name | date& Time              | PowerOutput         
----------+-------------------------+------------------
ACT0001   | 2013-07-21 01:00:00.000 | 196.852984494331   
ACT0001   | 2013-07-21 02:00:00.000 |   0   
xyz0001   | 2013-07-21 03:00:00.000 | 196.852984494331   
xyq0001   | 2013-07-21 04:00:00.000 | 196.958395639561 
xys0001   | 2013-07-21 05:00:00.000 |   0
xyd0001   | 2013-07-21 06:00:00.000 | 197.20098185022 
xye0001   | 2013-07-21 07:00:00.000 |   0 
xyg0001   | 2013-07-21 08:00:00.000 |   0     
cfg0001   | 2013-07-21 09:00:00.000 | 197.412144323522 
acb0001   | 2013-07-21 10:00:00.000 |   0 
bdf0001   | 2013-07-21 11:00:00.000 |   0 
olk0001   | 2013-07-21 12:00:00.000 | 196.886233049016

我有这张表，我正在尝试更新＆＃34; ZERO＆＃34;的地方的值。如果只有一个零，那么我可以更新表，但如果有连续的零，我发现很难更新表。

逻辑是：

（（先前值 - 下一个值）/前一个值）* 100 <5

如果这是真的那么它应该插入先前的值
（（上一个值 - 下一个值）/前一个值）* 100＆gt; = 5

如果这是真的那么它应该保持为零。

这是我到目前为止的代码：

with cte as
(
    SELECT  
        *,
        lead(pr_output,1) OVER (ORDER BY (select null)) As PreviousValue,
        lag(pr_output,1) OVER (ORDER BY (select null)) As NextValue
    FROM
        [dbo].[Mytable]
)
,ctee as
(
    select 
        *,
        abs((PreviousValue*100-NextValue*100)/NextValue) as CheckFlag
    from
        cte 
)
select
    Site_name,[DATE&Time],
    case 
        when pr_output <>0 then pr_output
        else
            case 
                when CheckFlag >= 5 then 0
                else PreviousValue
            end
    end as pr_output
from 
    ctee

我得到的错误是

遇到零错误。

请告诉我我做错了什么。如果他们是通过这种方式的另一种方式吗？

感谢任何帮助。

输出应该是：

Site_name | date& Time              | PowerOutput         
----------+-------------------------+------------------
ACT0001   | 2013-07-21 01:00:00.000 | 196.852984494331   
ACT0001   | 2013-07-21 02:00:00.000 | 196.852984494331   
xyz0001   | 2013-07-21 03:00:00.000 | 196.852984494331   
xyq0001   | 2013-07-21 04:00:00.000 | 196.958395639561 
xys0001   | 2013-07-21 05:00:00.000 | 196.958395639561
xyd0001   | 2013-07-21 06:00:00.000 | 197.20098185022 
xye0001   | 2013-07-21 07:00:00.000 |   0 
xyg0001   | 2013-07-21 08:00:00.000 |   0     
cfg0001   | 2013-07-21 09:00:00.000 | 197.412144323522 
acb0001   | 2013-07-21 10:00:00.000 |   0
bdf0001   | 2013-07-21 11:00:00.000 |   0 
olk0001   | 2013-07-21 12:00:00.000 | 196.886233049016

Answer 1

在除以之前需要检查NextValue是否为零..

希望这能解决你的问题。

with cte as
(
    SELECT  
        *,
        lead(pr_output,1) OVER (ORDER BY (select null)) As PreviousValue,
        lag(pr_output,1) OVER (ORDER BY (select null)) As NextValue
    FROM
        [dbo].[Mytable]
)
,ctee as
(
    select 
        *,
        abs((PreviousValue*100-NextValue*100)/(case when NextValue = 0 then 1 else NextValue end)) as CheckFlag
    from
        cte 
)
select
    Site_name,[DATE&Time],
    case 
        when pr_output <>0 then pr_output
        else
            case 
                when CheckFlag >= 5 then 0
                else PreviousValue
            end
    end as pr_output
from 
    ctee

如何使用多个case语句更新多个值null

1 个答案: