def up
Link.update_all("head_kind=replace(head_kind,'orvos','arvados')")
Link.update_all("tail_kind=replace(tail_kind,'orvos','arvados')")
def up
Link.update_all("head_kind=replace(head_kind,'orvos','arvados')")
Link.update_all("tail_kind=replace(tail_kind,'orvos','arvados')")