BulkUpsertExtensions can be used for inserting new contact extensions and updating existing contact extensions in the master_contact_extensions table.

This method takes a column list and a contactDatas array. All the data will be processed according to the columns list.

contact_key and address columns in master_contact_extensions table is mandatory and unique across all the extensions.
So, for all items in the request body, contact_key and address are mandatory parameters.

The users are allowed to update directly name,permission and channel columns in master_contact_extensions table. If the users need to update contact_key or address columns, they have to provide the values with new_contact_key or new_address properties.

Important Note
You can use insertIfNotExists property to insert new extension records to master_contact_extensions table. But contact extension insert operation is not available if you have new_contact_key or new_address property in the same request. You need to separate the operations into different requests. In the first request, you can update the contact_key or address column with new values than in the other request you can insert new records.

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