I am learning kibana but i would like to know how to perform the subtraction. For example, we have two fields "starting = 2018-05-15 12:20:03.400779 , ending=2018-05-15 12:20:03.360979" . Can please know is there anyway to calculate duration (ending - starting) as a field. i am having hard to implement it as scripted field. Any help would be appreciated.