hibernate中多对多设置
一段时间不用了，纯属记录，以防忘记了。。。
在hibernate中，多对多关系可以看成是2个 多对一的关系。
???? 在实体UserInfo和Teacher中，都设置many-to-many属性,
属性中需要设置主控方与被控方的inverse和cascade值
???? 出现问题：save the transient instance before flushing
???? 说明：t_s表，不需要单独建实体对象，是一张表
?
1 Hibernate: select nextval ('userinfo_id_seq') 2 Hibernate: select nextval ('teacher_id_seq') 3 Hibernate: select nextval ('userinfo_id_seq') 4 Hibernate: select nextval ('teacher_id_seq') 5 Hibernate: insert into userinfo (username, age, address, id) values (?, ?, ?, ?) 6 Hibernate: insert into teacher (username, id) values (?, ?) 7 Hibernate: insert into userinfo (username, age, address, id) values (?, ?, ?, ?) 8 Hibernate: insert into teacher (username, id) values (?, ?) 9 Hibernate: insert into t_s (u_id, t_id) values (?, ?)10 Hibernate: insert into t_s (u_id, t_id) values (?, ?)