B4J Question Is it BUG, that in debug mode no exception but release mode yes?

alwaysbusy

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• Aug 11, 2020

• #2

Have your tried swichting the condition? May have something to do with the casting.

B4X:

If "I" = szf.GetString("IdoszakielszIN") Then

Alwaysbusy

 

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rosippc64a

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• Aug 11, 2020

• #3

Yes, I tried, but fail. The solution was I give default value ("N") to this db field.

Here is the question not that, but whether it is normal that the same code works otherwise in debug mode as in release mode in B4J?

 

Last edited: Aug 11, 2020

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keirS

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• Aug 11, 2020

• #4

If you want to know whether a string is null it's quite easy:

Is ResultSet Column Null?:

R = JSQL.ExecQuery("select * from test2")
    Dim JO As JavaObject = R
    Do While R.NextRow
         Dim ISNull As Object =  JO.RunMethod("getObject",Array As Object("st2"))
         If ISNull = Null Then
             Log("String is Null")
        Else
            Log(R.GetString("st2"))
        End If
        
        
Loop

 

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rosippc64a

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• Aug 11, 2020

• #5

Thank you @keirS, interesting solution, I think will use, but additionally I would that null="I" comparison (doesn't matter it is a good or wrong) do work at the same manner in debug and release mode!

 

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rosippc64a

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• Aug 23, 2020

• #6

@Erel please check this out!

 

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Erel

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• Aug 23, 2020

• #7

Combining nulls with strings is problematic and not recommended. The problem is that in some cases the null is converted to "null" and in some cases it wont.

I expect this code to work properly:

B4X:

If "I" = szf.GetString("IdoszakielszIN") Then

 

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rosippc64a

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• Aug 23, 2020

• #8

Thank you @Erel you are right. That is interesting, since there was a moment when it failed (post #3), but now it works well.
As I wrote there was another solution giving default value to the database field, I just wondering what would be the reason of that, that b4j program works different in debug and release mode.

 

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