I find how to add a footer with some calculations of the data in my grid like for example
Now I want a specific calculation. I want to get the distinct values of a certain column. For example a book store. With the code above I can get the numbers of books I have in my store, but I also want the number of distinct authors of my store. I use this code for it:
The problem is that when I use the #text_filter, the custom author count doesn’t change like the #stat_count. How can I do that?