Salesforce Certified Data Architecture Practice Test 2026 – All-in-One Guide to Exam Mastery!

When using upsert with Data Loader for Contact records, a data architect should be aware of the potential issues with duplicate external ID values within the same CSV file. This scenario can lead to conflicts when the upsert operation is executed, as the Data Loader relies on the external ID to determine whether to update an existing record or insert a new one.

If there are multiple records in the CSV file that contain the same external ID, Data Loader cannot resolve which record to update, potentially leading to an error or unexpected outcomes. This means that maintaining unique external ID values is crucial to ensure the integrity of the data upload process and to avoid complications in the final dataset.

The other choices highlight valid concerns but do not directly address the most common error associated with upserting using external IDs. For instance, while having records that are both updated and inserted can lead to confusion, it is primarily the duplicate external IDs that are more likely to halt the process entirely, making it a more pressing concern.