[Mondrian] NullDenominatorProducesNull Property

Rushan rushan.chen at gmail.com
Tue Dec 9 16:12:44 EST 2008


The document,a s John pointed out, is out of date. I will make it match 
the code.

If the denominator values comes from an expression, you can also use the 
IIF function to turn 0 into Null if that is the semantics required.

Rushan

However, the
John V. Sichi wrote:
> michael.pflug at thomsonreuters.com wrote:
>>   Can I get some clarification about the purpose of the property 
>> NullDenominatorProducesNull?  On the Mondrian website and in comments 
>> the property is called NullOrZeroDenominatorProducesNull while the 
>> actual name of the property is NullDenominatorProducesNull.  The code 
>> using this property actually checks both the numerator and 
>> demoninator for null, but doesn’t check for zero.  I have a case 
>> where I want to catch a divide by zero and return null instead of 
>> “infinity” and it seems like this property should be the way to do it 
>> (see example below).  Does anyone know why the property was changed 
>> to exclude zero to begin with and are there objections to adding the 
>> check for zero back in?  
>
> This property was introduced when the discrepancy between Mondrian and 
> MSAS behavior was originally noticed.  The property was added as a 
> backward-compatibility flag to allow applications which had become 
> dependent on the original Mondrian behavior to keep working.
>
> There was some confusion about the property name and semantics, so it 
> went through a few iterations before settling on 
> NullDenominatorProducesNull.
>
> Rushan, it looks like mondrian/doc/configuration.html never got 
> updated to match the final state, leading to the mismatch Michael 
> noticed; can you fix that?
>
> Michael, I don't think further changes to the semantics of this 
> property would be the best approach, since that can break existing 
> reports; instead, perhaps some new UDF's which can be used to 
> explicitly request the desired semantics on a case-by-base basis?
>
> JVS
>
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