I have a dataset that has among other dimensions, contract id and original contract id. Each row has a contract id but may or may not have an original contract id. Contract ids are unique, but can become original contract ids for different contract ids. So, the same contract id may exist on another row as an original contract id, but only once. What I want to do is look at a contract id, and determine if that contract id exists as an original contract id on any other row in the data, then use that as a filter. Example:
|Contract ID||Original Contract ID|
In this example, I would want contract ids 110011 and 164222 to be marked as '0' because they also appear elsewhere as an original contract id. Contract ids 122333, 195544, and 188550 would be marked as '1' because they do not appear as an original contract id in the data.
Is this possible, and if so what is the best way to accomplish this?