To set up my store I have used the WIX App Store collection. No I want to connect this store to an external database. If I go the products database (Corvid) all the data is ‘grey/blocked’ means read-only, so I cannot connect the data to an external database. I want to synchronize only the quantity in stock. I also have tried to add a new reference field to the database, but that’s not possible. What can I do?
When you add Wix Stores app to your site, it automatically adds the collections for it which are all read only.
https://support.wix.com/en/corvid-by-wix/wix-stores-with-corvid
https://www.wix.com/corvid/reference/wix-stores.html
https://www.wix.com/corvid/reference/wix-stores-backend.html
To have your own external database for a store, you will need to create your own store or add those products to the Wix Store itself.