Because I am learning QGIS and I had to delete records in a attribute table, I made a copy (project > save as > saving as 'project_copy' before deleting attributes. To be safe...
So I deleted the attributes in the project_copy. But to my surprise, I see that the deleted attributes are also deleted in the original project!? There seems to be a link between both projects although I didn't ask for...
Did I really lose the deleted attributes?
Is there a way to restore the deleted attributes?