How tofilter out empty entries when creating a pie chart?

Question

When I create pie chart in Kibana and use Split Slices by Term called DataType, is it possible to filter out all cases when DataType is "". Unfortunately, if I go to Filters menu in the top of a chart, I can see only the non-empty values of DataType. The filter does exist neither helps, because DataType always exists, just in some cases it is equal to "" instead of, e.g. DT1, DT2, etc.

Answer 1

Look at exist query, search for "mapping", then you will see that you can define the null value, you can define that null value is empty string, then in exist query it's will filter out