Hi,

> How can I get NULL from SUM when a value is NULL?
>
> I know that aggregate functions only use non null values.
> My problem is different. I want to sum a list of values, but if one or
> more is null, then I would need to get NULL.
>
> For example, table person:
>
> Name, Weight
> -----,----
> John, 50
> Paul, 100
> Mary, NULL
>
>
> If I do "SELECT SUM(Weight) FROM Persons", I get 150.
> I would like to get NULL since we do not know the weight of Mary, and then
> it is not possible to get the total weight.
> How can I do it?

I guess you have to create a Selectable Stored Procedure for it that
cycles through the results of your query and sums the WEIGHT, breaking
when it hits NULL and returning NULL then.

With regards,

Martijn Tonies
Upscene Productions
http://www.upscene.com

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