Maybe I'm not interested in the scores, I just want to know how many exams friend here took. This is also something
you can easily find out in the project
phase, you could add some scores here
and then we can use a helpful operator, the size operator which calculates the length of an array.
And here we can simply input the well name of the field which holds the array or again hardcode an
array in here if you wanted to, for whatever reason.
So here I will point at exam scores and I will calculate the size for that array and store it in
num scores.
So if I now copy that entire command here,
you see we get three for every user because every user happens to have three exams in our dataset here
but this is how you can get the length of an array, with $size operator and then a pointer
to the field which holds the array for which you want to calculate the length
and then this gets stored in a new field.