Some times we have requirement where we need to forcefully show expression labels if there is no value for the expression.
When ever we have multiple expression in our chart and if one of expression is having null value or no values.. then the expression label is auto hidden by qlikview..
But this functionality can be overridden by a simple solution using ALT() function.
just enclose your expression inside ALT()... and alt() will replace the null or undefined expression values to specified once.
Say i have a expression Sum(V1) then we need to wright Alt(Sum(V1),0).. if the sum(V1) is null or undefined the value will be replaced by 0 and expression lable will be visible...
Hope this small but powerful function ease your life...