For example let’s look at the data table below. It contains the data for drug samples given by sales reps to physicians. In order from left to right the columns are 1) the visiting reps’ name, 2) the visited physicians’ name, 3) the date of visit and 4) the number of samples given.
Now if you were to find out, in a single formula, the total number of samples left by reps containing ‘Andrew’ in their name and visit date between 1st Jan and 15th Jan 2012 (both inclusive)– how would you do that?
Well… the answer is array formula. Continue reading