Article filter properties - csv upload or database tables

Hi there, i posted this question in the german forum already but wouldn’t get an answer, so here is my question:

i added a new filter option for our articles. Since we have about 2.5k articles i want to automate the setting of this property. Sadly the API could not handle so many calls, the connection timed out. So i would like to know if there is an option to do this via csv-uploads (it should only change existing articles, not adding new ones) or via a mysql query (i didn’t find the required tables to join)

Any help would be greatly appreciated