Filter showing NULL for one variable which is a string by the way (other 4 variables are numbers)
So I created a filter wrt. 6 classes in a school (1,2,3,4,5,F-Klass).
It is labeled as TEXT when creating as a datasource.
all is fine except F-Klass is showing as NULL inside filter.
You can checkout the created dash here. How to fix it so that it doesn't show as NULL