I have a List of webinar registrants. The webinars are in different professional education areas. If I import a CSV file of registrants with the custom property field Course Taken and the input on file import in that field being [“course_a”], when I later import another CSV file with Course Taken as [“course-b”] and the registrant previously took course_a, will the import override where [“course-a”] exists or will the import append and extend the list array to read [“course_a”],[“course_b”] ?
Solved
Building a custom property list array
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Best answer by saulblum
It will overwrite the existing properties.
If you use the API, you can append values:
https://developers.klaviyo.com/en/reference/spawn_bulk_profile_import_job
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