When trying to upload Training Requirement records via Vault Loader, it shows the following error: Batch Error: Another resource already exists with [external_id__v=XXXX].
However, there are no existing Training Requirement records at all.
When a Training Requirement is created, the external_id__v value is copied to external_id__v on the newly created training_content_set_v record. Even though all the Training Requirement records are deleted, there is still a Training Content Set record with the External ID that is specified in the loader CSV file. This prevents the Training Requirement records from being uploaded successfully.
To fix this, the Training Content Set record needs to be deleted.
Vault Help Documentation: N/A