I know that Rest & Soap API can be used to import data into Marketing Cloud from an external system, but does any of them offer the possibility to import into multiple Data Extensions from a single API Call? Or do you need a separate call for each Data Extension?
I was looking at the official documentation for the Rest API Async Upsert and the Soap API Upsert, but this information is not mentioned. Do you have any idea if this is possible?
Thank you!