static <A extends Concept> A nuLike uniq_sync(final Class<A> c, fO... params) {
  ret uniq_sync(db_mainConcepts(), c, params);
}

static <A extends Concept> A nuLike uniq_sync(Concepts concepts, Class<A> c, fO... params) {
  ret withDBLock(concepts, func -> A { uniq(concepts, c, params) });
}