Transaction Lists [Draft]
Overview
When creating an audience list, if your list has at least one aggregated column, it will be considered a transaction list. It doesn’t matter if there is PII within that list or not.
These lists can be used to create segments based on different columns present on the lists.
More technical information
Unless a unique key is specified when creating the list - the first added PII attribute will be the unique key on that list.
If you specify another unique key, the PII attribute will be removed from the unique key and you will have to select the PII attribute as well if you want it as a unique key.