表数据重复 - MySQL

Question

对于cost_center_code列中的重复数据我该怎么办？

这是我的疑问：

@Controller
public class TrafficController {

    ....
    @Autowired
    private ApplicationContext context;

    @Autowired
    public UserService userService;

    public TrafficService trafficService;
    ....

    @RequestMapping(value="/api/traffic/stations")
    public List<....> getNearStations(HttpServerletRequest req) {
        String userId = SessionAttrs.getUserId(req.getSession());
        User user = userSerivce.getUser(userId);

        trafficService = (TrafficService) context.getBean(Class.forName("com.myservice.service.impl.TrafficService_"+user.house.apt.address.area_code + "_Impl"));
        return trafficService.getStations(user.house.apt.latitude, user.house.apt.longitude, 300, 2);

    }
}