不使用字符串的条件查询

Question

@Repository
public interface AddressRepository extends JpaRepository<Address, Long>
{       
    @Query("SELECT a.state FROM address_table a WHERE a.city = '' ") 
    String getState();
    // the blank city should be the city from user.setCity (ua.getCity())
}

@Component 
public class AddressManager
{
    @Autowired
    private AddressRepository aRepo;

    @Autowired
    private UserRepository uRepo    

    public void save(UserAddressDto ua)
    {               
        User user = new User();
            
        user.setCity (ua.getCity());
        user.setState(aRepo.getState());
                    
        uRepo.save(user);
    }
}

Answer 1

如果city是字符串，则：

地址存储库

@Query("SELECT a.state FROM address_table a WHERE a.city = :city ", nativeQuery = true) 
String getState(@Param("city") String city);

AddressManager

user.setCity (ua.getCity());
user.setState(aRepo.getState(ua.getCity()));