java - 使用 java hibernate 插入

Question

我有一个客户

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "cl_id")
private Long clId;

@JoinColumn(name = "vl_id", referencedColumnName = "vl_id")
@ManyToOne
private City cityId;

每当我以这种方式创建新客户端时:

Client c = new Client();
c.setCityId(new City());

并坚持下去。如果城市不存在，它也不会持续存在。除非 City 对象有 Id ，否则城市不会被持久化吗？

Answer 1

您必须启用cascading :

@JoinColumn(name = "vl_id", referencedColumnName = "vl_id")
@ManyToOne(cascade=CascadeType.PERSIST)
private City cityId;