puzzle... (1 Viewer)

A

ariel81

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• Mar 1, 2007

• #1

i have this code:

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 If IsNull(rs![tblFltTotalJobsAE] Or rs![tblFltTotalJobsEI] Or rs![tblFltTotalJobsRC]) = False Then
             a = a + rs![tblFltTotalJobsAE]
             b = b + rs![tblFltTotalJobsEI]
             c = b + rs![tblFltTotalJobsRC]
             d = a + b + c
             
          
                 f("test2") = d
            
              End If

the result of the abv code eg:
rs![tblFltTotalJobsAE] <- 2
rs![tblFltTotalJobsEI] <- 3
rs![tblFltTotalJobsEI] <- 4
f("test2") = 9 , the result will be 9 (correct!)

if any of the rs![ ] is a null,
rs![tblFltTotalJobsAE] <- 2
rs![tblFltTotalJobsEI] <-
rs![tblFltTotalJobsEI] <- 4
f("test2") = **empty data** , the result should be 6 but the textbox is blank.

why the abv code doesn't seems to add up records whenever any of the records is empty?

 

neileg

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• Mar 1, 2007

• #2

Null isn't the same as zero. Look at the Nz() function.

 

B

Bat17

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• Mar 1, 2007

• #3

If IsNull(rs![tblFltTotalJobsAE] Or rs![tblFltTotalJobsEI] Or rs![tblFltTotalJobsRC]) = False Then

this will always return false as you are asking a logic question and you will get either a 0 or 1 retuned by the brackets

Peter

 

RuralGuy

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• Mar 1, 2007

• #4

Peter,
I can't come up with a test right now but I believe *any* non 0 value will be interpreted and a True.

 

B

Bat17

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• Mar 1, 2007

• #5

Just done a quick check

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Dim a, b, c
Dim d As Boolean
d = (a Or b Or c)
Debug.Print d

Prints False

Peter

 

B

Bat17

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• Mar 1, 2007

• #6

The point really is that the logic test will give 1 or 0 so isnull will alway answer False

Peter

 

RuralGuy

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• Mar 1, 2007

• #7

Hi Peter,
Try this one:

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Dim a, b, c
Dim d As Boolean
a = 1
d = (a Or b Or c)
Debug.Print d

 

RuralGuy

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• Mar 1, 2007

• #8

Hi Peter,
How about:

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Dim d As Boolean
d = IsNull(Null Or Null Or Null)
Debug.Print d

 

B

Bat17

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• Mar 1, 2007

• #9

oop
Always thought a variant was a null not an "" before it was assigned.

Suppose that this is a case of Nulls propagating again, but then why does it not always end up with a null

Peter

 

RuralGuy

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• Mar 1, 2007

• #10

OR does not propagate a null but + does.