First of all variables are columns and observations are rows. Having a variable called variable is just going to lead to all sorts of confusion. As it has with me. I'm not really sure what you are looking for.
I didnt name the variable "variable" i was just using that as an example. The bold variable, is the column that I am tryin to capture a specific value. The "value" column, is the column i want to determine if it is not null. That is why I had those two columns bold. I hope this helped a little. Sorry for the confusion.