topic Difference between null and zero in QlikView

Difference between null and zero

Tue, 19 May 2009 19:55:28 GMT

Hi,

I have a widget which uses this code to hide the widget if data is unavailable. (NULL)

if(isnull(Value),-1,0)

The problem is that when the value is 0, it seems to hide the widget.

Why is this? surely qlikview disinguishes between 0 and null.

Difference between null and zero

Anonymous — Tue, 19 May 2009 20:06:33 GMT

You're right, there is a clear difference between null and 0 (and empty string as well). Check the values of the Value. If you think there is still a problem, post an example here.

Difference between null and zero

johnw — Wed, 20 May 2009 00:51:52 GMT

If you're using 64-bit, there may not be such a clear difference, and it isn't a good idea to use isnull(). It seems that they went for performance over functionality and backwards-compatibility. If you're using 64-bit, I'd use =len(Value)<1. For that matter, in case you ever migrate to 64-bit, I'd get in the habit of not using isnull().