Question

我试图通过使用“条款”进行询问,但在这方面存在一些问题。

S_E1:

这里的数据是43。

select RECORD_TIMESTAMP as DateRecorded, ROUND (S_E1 ,2 )as S_E1
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM  
                           and  5/17/2012 12 :00 AM 
And ( S_E1 Between 10 And 100 )

第二张S_E:

这里的数据是68。

select RECORD_TIMESTAMP as DateRecorded, ROUND (S_E2 ,2 )as S_E2
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM 
                           and  5/17/2012 12 :00 AM 
And ( S_E2 Between 10 And 100 )

<<>Problem>:

但是,如果把这些问题与询问合并在一起,则提供错误的数据。这给我带来了73个增长。我认为,它应当给111个牢房。

select RECORD_TIMESTAMP as DateRecorded, 
       ROUND (S_E2 ,2 )as S_E2, 
       ROUND (S_E1 ,2 ) as S_E1
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM 
                           and  5/17/2012 12 :00 AM 
And ( S_E2 Between 10 And 100) 
and (S_E1 Between 10 And 100  )

请在此谈谈我错失之处。

Answer 1

使用<代码>OR而不是AND

SELECT RECORD_TIMESTAMP AS DateRecorded, 
       Round (S_E2, 2)  AS S_E2, 
       Round (S_E1, 2)  AS S_E1 
FROM   TBL_SENSORS 
WHERE  RECORD_TIMESTAMP BETWEEN  4/28/2012 12 :00 AM  AND  5/17/2012 12 :00 AM  
       or ( S_E2 BETWEEN 10 AND 100 ) 
       or ( S_E1 BETWEEN 10 AND 100 )

在询问中,没有保证你将获得111份记录,因为有两种情况的共同记录。

条件1 - <代码>(S_E2 BETWEEN 10 and 100)

条件2 - <代码>(S_E1 BETWEEN 10 and 100)

或

使用工会查阅所有记录的所有查询(111)。

select RECORD_TIMESTAMP as DateRecorded, ROUND (S_E1 ,2 )as S_E1, 0 as S_E2
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM  and  5/17/2012 12 :00 AM 
And ( S_E1 Between 10 And 100 )

UNION ALL

select RECORD_TIMESTAMP as DateRecorded, 0 as S_E1, ROUND (S_E2 ,2 ) as S_E2
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM 
and  5/17/2012 12 :00 AM 
And ( S_E2 Between 10 And 100 )

Answer 2

我认为,你应在这两份声明之间形成联盟,或者说你应该使用“或”而不是“或”。

select RECORD_TIMESTAMP as DateRecorded,ROUND (S_E2 ,2 )as S_E2,ROUND (S_E1 ,2 )as S_E1 from TBL_SENSORS Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM  and  5/17/2012 12 :00 AM  AND (( S_E2 Between 10 And 100) OR(S_E1 Between 10 And 100 ))

Answer 3

2. 改变血压逻辑,将外心放在一边,取而代之;

select RECORD_TIMESTAMP as DateRecorded, 
       ROUND (S_E2 ,2 )as S_E2, 
       ROUND (S_E1 ,2 ) as S_E1
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM 
                           and  5/17/2012 12 :00 AM 
And (( S_E2 Between 10 And 100) 
OR (S_E1 Between 10 And 100  ))

Answer 4

问题在于S_E2和S_E1的限制。

为了与大家一样工作,你必须使用<代码>。 UNION ALL:

select RECORD_TIMESTAMP as DateRecorded, ROUND (S_E1 ,2 )as S_E
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM  and  5/17/2012 12 :00 AM 
And ( S_E1 Between 10 And 100 )

UNION ALL

select RECORD_TIMESTAMP as DateRecorded, ROUND (S_E2 ,2 )as S_E
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM 
and  5/17/2012 12 :00 AM 
And ( S_E2 Between 10 And 100 )

或您使用<代码>OR代替AND 类似:

select RECORD_TIMESTAMP as DateRecorded, 
       ROUND (S_E2 ,2 )as S_E2, 
       ROUND (S_E1 ,2 ) as S_E1
from TBL_SENSORS
Where RECORD_TIMESTAMP Between  4/28/2012 12 :00 AM 
                           and  5/17/2012 12 :00 AM 
And ( (S_E2 Between 10 And 100) OR (S_E1 Between 10 And 100)  )

由于限制的唯一区别是S_E1和S_E2栏,如果你使用<代码>AND<>代码,你就表示,所有记录都必须遵守这两项限制。在分开的询问中,他们只尊重他们,因此,在主问中必须如此。

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