With the new GDPR regulations we need to reconfirm consent for all our customers and delete/amend those customers who do not give consent.

I think what i need to do is to replace all personal information with something like  xxxx.  

I expect there is going to be a large number of those customers so wondering if anyone has a way to sync a master spreadsheet (or csv) to the global customer table. 

Not sure if the "Delete Global Customer" does something like this but it does not allow me to import a table.

Appreciate any ideas you have.