| order_number |
|---|
| 100 |
| 101 |
| 101 |
| 102 |
| 103 |
| 103 |
| 103 |
| 104 |
| 104 |
I'd like to create an expression which counts instances where order_number occurs only once. Example - 100 and 102 do not repeat, while 101, 103 and 104 have multiple instances. The expected result is 2.
I've tried count({<count(order_number)={1}>}order_number) but does not seem to work.