hibernate双边关系（多对一和一对多）

Hibernate: Running hbm2ddl schema export Hibernate: import file not found: /import.sql Hibernate: exporting generated schema to database Hibernate: alter table tb_student drop foreign key FK9007E96A302AC3E9 Hibernate: Unsuccessful: alter table tb_student drop foreign key FK9007E96A302AC3E9 Hibernate: Table 'hibernate2.tb_student' doesn't exist Hibernate: drop table if exists tb_class Hibernate: drop table if exists tb_student Hibernate: create table tb_class (id integer not null auto_increment, name varchar(255), primary key (id)) Hibernate: create table tb_student (id integer not null auto_increment, name varchar(255), sex varchar(255), class_id integer, primary key (id)) Hibernate: alter table tb_student add index FK9007E96A302AC3E9 (class_id), add constraint FK9007E96A302AC3E9 foreign key (class_id) references tb_class (id) Hibernate: schema export complete Hibernate: Running hbm2ddl schema export Hibernate: import file not found: /import.sql Hibernate: exporting generated schema to database Hibernate: alter table tb_student drop foreign key FK9007E96A302AC3E9 Hibernate: drop table if exists tb_class Hibernate: drop table if exists tb_student Hibernate: create table tb_class (id integer not null auto_increment, name varchar(255), primary key (id)) Hibernate: create table tb_student (id integer not null auto_increment, name varchar(255), sex varchar(255), class_id integer, primary key (id)) Hibernate: alter table tb_student add index FK9007E96A302AC3E9 (class_id), add constraint FK9007E96A302AC3E9 foreign key (class_id) references tb_class (id) Hibernate: schema export complete Hibernate: Running hbm2ddl schema export Hibernate: import file not found: /import.sql Hibernate: exporting generated schema to database Hibernate: alter table tb_student drop foreign key FK9007E96A302AC3E9 Hibernate: drop table if exists tb_class Hibernate: drop table if exists tb_student Hibernate: create table tb_class (id integer not null auto_increment, name varchar(255), primary key (id)) Hibernate: create table tb_student (id integer not null auto_increment, name varchar(255), sex varchar(255), class_id integer, primary key (id)) Hibernate: alter table tb_student add index FK9007E96A302AC3E9 (class_id), add constraint FK9007E96A302AC3E9 foreign key (class_id) references tb_class (id) Hibernate: schema export complete Hibernate: Running hbm2ddl schema export Hibernate: import file not found: /import.sql Hibernate: exporting generated schema to database Hibernate: alter table tb_student drop foreign key FK9007E96A302AC3E9 Hibernate: drop table if exists tb_class Hibernate: drop table if exists tb_student Hibernate: create table tb_class (id integer not null auto_increment, name varchar(255), primary key (id)) Hibernate: create table tb_student (id integer not null auto_increment, name varchar(255), sex varchar(255), class_id integer, primary key (id)) Hibernate: alter table tb_student add index FK9007E96A302AC3E9 (class_id), add constraint FK9007E96A302AC3E9 foreign key (class_id) references tb_class (id) Hibernate: schema export complete Hibernate: Running hbm2ddl schema export Hibernate: import file not found: /import.sql Hibernate: exporting generated schema to database Hibernate: alter table tb_student drop foreign key FK9007E96A302AC3E9 Hibernate: drop table if exists tb_class Hibernate: drop table if exists tb_student Hibernate: create table tb_class (id integer not null auto_increment, name varchar(255), primary key (id)) Hibernate: create table tb_student (id integer not null auto_increment, name varchar(255), sex varchar(255), class_id integer, primary key (id)) Hibernate: alter table tb_student add index FK9007E96A302AC3E9 (class_id), add constraint FK9007E96A302AC3E9 foreign key (class_id) references tb_class (id) Hibernate: schema export complete