text: ALTER TABLE public.processor_version
      ALTER COLUMN "publisher_id" drop NOT NULL
  ;
  
  ALTER TABLE public.data_processor
      DROP CONSTRAINT IF EXISTS data_processor_slug_unique;
  ALTER TABLE public.data_processor
      DROP CONSTRAINT IF EXISTS data_processor_author_slug_unique;
  ALTER TABLE public.data_processor
      ADD CONSTRAINT data_processor_author_slug_unique UNIQUE (author_id, slug);
  