Contact Import

[Yash]

Hi Everyone,

I have a list of 150K contacts and I have been asked to update a specific field within the contact record for the contacts that exists in the list. We need the contact record's field value to be updated with the corresponding column value from the spreadsheet only when the field value is empty or in other words if the field is already populated then it shouldn't be updated.

Thanks

[JD_Nelson]

I would separate your list by conditions and do multiple uploads. Check email addresses for existing leads and process those separately: one for those that have a value and should update the field, and one for those that don't have the value and therefore should not include that column nor update it when uploading. THEN you can process your net new list of leads separately where they get the value if they have it and it's null if they don't (by default).

[Katja_Keesom · Accepted solution]

You could actually do two things:

- Do your list upload using the List Import Mode "Skip new leads and updates". This should not create any new people in Marketo and also not update the field if a value is already there.

- Protect the field you are updating in the Admin section from Uploads through list imports.

If you apply those safeguards you should be fine, but I would strongly recommend to test the process on a small batch before processing this enormous amount.

[Yash]

Thanks so much @Katja_Keesom 

I will make sure to test process for small volume before I mass update the whole list.