06 2021 档案

Jpa @ManyToMany

摘要：代码 @Entity public class Student { @Id private String id; @ManyToMany(mappedBy = "students") private List<Teacher> teachers; } @Entity public class Tea 阅读全文

posted @ 2021-06-04 16:42 jason47 阅读(171) 评论(0) 推荐(0) 编辑

Jpa @ManyToOne

摘要：案例 public class Robot{ @ManyToOne//(fetch=FetchType.LAZY)// @JoinColumn(name="robottype_id") private RobotType robotType; } 1.使用fetch会抛异常阅读全文

posted @ 2021-06-04 16:19 jason47 阅读(119) 评论(0) 推荐(0) 编辑

Jpa @OneToMany

摘要：案例 @Entity @Table(name = "robot") public class RobotEntity { @OneToMany//(orphanRemoval=true) @JoinColumn(name = "robot_id") private List<Material> ro 阅读全文

posted @ 2021-06-04 16:16 jason47 阅读(87) 评论(0) 推荐(0) 编辑