You can't select NULL, it's not a value / symbol you can select.
It seems that your record set shows identificacion values that have no relation to Ca... (what ever your dimension field is named like) field values.
If you want to identify these identificacion values (or other related field values like a primary key ID), you can first select all Cam.. values, i.e. Inbound, Mail, Outbound, Ubicabilidad and then select the exluded values on field identificacion.
I had just this question:
This works beautifully - when I make it a sheet Trigger
Is there a way of doing the same thing in Set Analysis? For example
The selections are: Null, Tinted, Normal
I want :
Count(widgets) when selection = NULL or selection = NORMAL
Count(widgets) when selection <> Tinted
Thank you for your help
Indeed! In fact "Null" is a rather controversial concept. If you really want to dig further (but I'm leaving the Qlik domain now) I can highly recommend these two blog posts: