How to stop hibernate to do select before insert in child table in many to one mapping?

    I have a student table :

    @Entity
    @Table
    @NoArgsConstructor
    @AllArgsConstructor
    @Builder
    @Data
    @IdClass(StudentId.class)

    public class Student implements Persistable<StudentId> {

        @Id
        private String studentUuid;

        @Id
        private String studentName;

        @Column
        private String sex;

        public Student(String studentUuid,String studentName){

            this.studentUuid = studentUuid;
            this.studentName = studentName;
        }

        @ManyToOne(fetch = FetchType.LAZY)
        @JoinColumns({
                @JoinColumn(
                        name = "classUuid",referencedColumnName = "classUuid"),
                @JoinColumn(
                        name = "className",referencedColumnName = "className")
        })
        private Class className;


        @Override
        public StudentId getId() {
            return new StudentId().builder().studentName(studentName).studentUuid(studentUuid).build();
        }

        @Override
        public boolean isNew() {
            return true;
        }
    }

@Entity
@Table
@Builder
@NoArgsConstructor
@AllArgsConstructor
@Data
@IdClass(ClassId.class)
public class Class implements Persistable<ClassId> {


    @Id
    private String classUuid;

    @Id
    private String className;

    @Column
    private String classRoomNo;

    @Column
    private String classSize;

    @OneToMany(mappedBy = "className",cascade = CascadeType.ALL,fetch = FetchType.LAZY)
    private List<Student> studentList;

    @Override
    public ClassId getId() {
        return new ClassId().builder().className(className).classUuid(classUuid).build();
    }

    @Override
    public boolean isNew() {
        return true;
    }
}