Sets are used to count the number of unique elements in a group, for example, the number of unique visitors to your site
therefore you would expect to be able to insert 'user id' for example as a value of some set metric that counts the number of unique users.
Since the metric function excepts only numeric values that feature can't be achieved.
From datadog documentation:
therefore you would expect to be able to insert 'user id' for example as a value of some set metric that counts the number of unique users. Since the metric function excepts only numeric values that feature can't be achieved.