Message
The selected unique identifier field is not unique.
Description
The field specified in the Unique identifier parameter must meet the following requirements:
- The field must exist in the feature layer or table to be updated.
- The field must contain all unique values.
- The field must be set as unique on the item page.
Solution
Go to the item details page for the feature layer or table to update and verify the following:
- The field exists in the feature layer or table.
- The field is set to unique. To learn more about setting unique fields, see Add a unique constraint to a field.
If you're unsure whether the field contains unique values, use the Remove duplicates tool to ensure that all records are unique.