大数据时代：如何节省存储成本

import java.util.List;
import javax.annotation.Resource;
import org.hibernate.SessionFactory;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;

import com.hx.ssh.bean.Login;
import com.hx.ssh.service.LoginService;

@Transactional
public class LoginServiceImpl implements LoginService {
 
 @Resource private SessionFactory sessionFactory;

 public void delete(int id) {
  // TODO Auto-generated method stub
        sessionFactory.getCurrentSession().delete(
          sessionFactory.getCurrentSession().load(Login.class, id));
 }
    @Transactional(propagation=Propagation.NOT_SUPPORTED,readOnly=true)
 public Login getLogin(int id) {
  // TODO Auto-generated method stub
  return (Login)sessionFactory.getCurrentSession().get(Login.class, id);
 }
   @Transactional(propagation=Propagation.NOT_SUPPORTED,readOnly=true)
   @SuppressWarnings("unchecked")
 public List<Login> getLogins() {
  // TODO Auto-generated method stub
  return sessionFactory.getCurrentSession().createQuery("from login as a").list();
 }

 public void save(Login login) {
  // TODO Auto-generated method stub

  this.sessionFactory.getCurrentSession().persist(login);
 }

 public void update(Login login) {
  // TODO Auto-generated method stub
  this.sessionFactory.getCurrentSession().merge(login);

 }

}