Hibernate 有 2 个线程，1 个出现错误答案

【问题标题】：Hibernate have 2 Threads and one getting errorHibernate 有 2 个线程，1 个出现错误
【发布时间】：2015-06-27 20:27:45
【问题描述】：

当 Hibernate 在 DB 中创建架构时，我有以下输出：

21:22:25,518 INFO  [stdout] (ServerService Thread Pool -- 13) Hibernate: 
21:22:25,518 INFO  [stdout] (ServerService Thread Pool -- 13)     alter table Contacto 
21:22:25,518 INFO  [stdout] (ServerService Thread Pool -- 13)         drop 
21:22:25,518 INFO  [stdout] (ServerService Thread Pool -- 13)         foreign key FK_5jh2jf636mhuh77q4hwl1i2w0
21:22:25,519 INFO  [stdout] (ServerService Thread Pool -- 50) Hibernate: 
21:22:25,519 INFO  [stdout] (ServerService Thread Pool -- 50)     alter table Contacto 
21:22:25,519 INFO  [stdout] (ServerService Thread Pool -- 50)         drop 
21:22:25,519 INFO  [stdout] (ServerService Thread Pool -- 50)         foreign key FK_5jh2jf636mhuh77q4hwl1i2w0
21:22:25,587 INFO  [stdout] (ServerService Thread Pool -- 13) Hibernate: 
21:22:25,587 INFO  [stdout] (ServerService Thread Pool -- 13)     drop table if exists Contacto
21:22:25,596 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) HHH000389: Unsuccessful: alter table Contacto drop foreign key FK_5jh2jf636mhuh77q4hwl1i2w0
21:22:25,596 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) Can't DROP 'FK_5jh2jf636mhuh77q4hwl1i2w0'; check that column/key exists
21:22:25,597 INFO  [stdout] (ServerService Thread Pool -- 50) Hibernate: 
21:22:25,597 INFO  [stdout] (ServerService Thread Pool -- 50)     drop table if exists Contacto
21:22:25,600 INFO  [stdout] (ServerService Thread Pool -- 13) Hibernate: 
21:22:25,600 INFO  [stdout] (ServerService Thread Pool -- 13)     drop table if exists Usuario
21:22:25,600 INFO  [stdout] (ServerService Thread Pool -- 50) Hibernate: 
21:22:25,601 INFO  [stdout] (ServerService Thread Pool -- 50)     drop table if exists Usuario
21:22:25,604 INFO  [stdout] (ServerService Thread Pool -- 13) Hibernate: 
21:22:25,604 INFO  [stdout] (ServerService Thread Pool -- 13)     create table Contacto (
21:22:25,604 INFO  [stdout] (ServerService Thread Pool -- 13)         id integer not null,
21:22:25,605 INFO  [stdout] (ServerService Thread Pool -- 13)         email varchar(255),
21:22:25,605 INFO  [stdout] (ServerService Thread Pool -- 13)         nombre varchar(255),
21:22:25,605 INFO  [stdout] (ServerService Thread Pool -- 13)         telefono varchar(255),
21:22:25,605 INFO  [stdout] (ServerService Thread Pool -- 13)         usuario_cuenta varchar(255),
21:22:25,605 INFO  [stdout] (ServerService Thread Pool -- 13)         primary key (id)
21:22:25,605 INFO  [stdout] (ServerService Thread Pool -- 13)     )
21:22:25,606 INFO  [stdout] (ServerService Thread Pool -- 50) Hibernate: 
21:22:25,606 INFO  [stdout] (ServerService Thread Pool -- 50)     create table Contacto (
21:22:25,606 INFO  [stdout] (ServerService Thread Pool -- 50)         id integer not null,
21:22:25,606 INFO  [stdout] (ServerService Thread Pool -- 50)         email varchar(255),
21:22:25,606 INFO  [stdout] (ServerService Thread Pool -- 50)         nombre varchar(255),
21:22:25,606 INFO  [stdout] (ServerService Thread Pool -- 50)         telefono varchar(255),
21:22:25,607 INFO  [stdout] (ServerService Thread Pool -- 50)         usuario_cuenta varchar(255),
21:22:25,607 INFO  [stdout] (ServerService Thread Pool -- 50)         primary key (id)
21:22:25,607 INFO  [stdout] (ServerService Thread Pool -- 50)     )
21:22:25,625 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) HHH000389: Unsuccessful: create table Contacto (id integer not null, email varchar(255), nombre varchar(255), telefono varchar(255), usuario_cuenta varchar(255), primary key (id))
21:22:25,625 INFO  [stdout] (ServerService Thread Pool -- 13) Hibernate: 
21:22:25,625 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) Table 'contacto' already exists
21:22:25,626 INFO  [stdout] (ServerService Thread Pool -- 13)     create table Usuario (
21:22:25,626 INFO  [stdout] (ServerService Thread Pool -- 13)         cuenta varchar(255) not null,
21:22:25,626 INFO  [stdout] (ServerService Thread Pool -- 13)         apellidos varchar(255),
21:22:25,627 INFO  [stdout] (ServerService Thread Pool -- 13)         email varchar(255),
21:22:25,627 INFO  [stdout] (ServerService Thread Pool -- 13)         nombre varchar(255),
21:22:25,627 INFO  [stdout] (ServerService Thread Pool -- 13)         password varchar(255),
21:22:25,628 INFO  [stdout] (ServerService Thread Pool -- 13)         primary key (cuenta)
21:22:25,628 INFO  [stdout] (ServerService Thread Pool -- 13)     )
21:22:25,628 INFO  [stdout] (ServerService Thread Pool -- 50) Hibernate: 
21:22:25,629 INFO  [stdout] (ServerService Thread Pool -- 50)     create table Usuario (
21:22:25,629 INFO  [stdout] (ServerService Thread Pool -- 50)         cuenta varchar(255) not null,
21:22:25,629 INFO  [stdout] (ServerService Thread Pool -- 50)         apellidos varchar(255),
21:22:25,629 INFO  [stdout] (ServerService Thread Pool -- 50)         email varchar(255),
21:22:25,630 INFO  [stdout] (ServerService Thread Pool -- 50)         nombre varchar(255),
21:22:25,630 INFO  [stdout] (ServerService Thread Pool -- 50)         password varchar(255),
21:22:25,630 INFO  [stdout] (ServerService Thread Pool -- 50)         primary key (cuenta)
21:22:25,630 INFO  [stdout] (ServerService Thread Pool -- 50)     )
21:22:25,639 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) HHH000389: Unsuccessful: create table Usuario (cuenta varchar(255) not null, apellidos varchar(255), email varchar(255), nombre varchar(255), password varchar(255), primary key (cuenta))
21:22:25,639 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) Table 'usuario' already exists
21:22:25,640 INFO  [stdout] (ServerService Thread Pool -- 50) Hibernate: 
21:22:25,640 INFO  [stdout] (ServerService Thread Pool -- 50)     alter table Contacto 
21:22:25,640 INFO  [stdout] (ServerService Thread Pool -- 50)         add constraint FK_5jh2jf636mhuh77q4hwl1i2w0 
21:22:25,641 INFO  [stdout] (ServerService Thread Pool -- 50)         foreign key (usuario_cuenta) 
21:22:25,641 INFO  [stdout] (ServerService Thread Pool -- 50)         references Usuario (cuenta)
21:22:25,641 INFO  [stdout] (ServerService Thread Pool -- 13) Hibernate: 
21:22:25,641 INFO  [stdout] (ServerService Thread Pool -- 13)     alter table Contacto 
21:22:25,642 INFO  [stdout] (ServerService Thread Pool -- 13)         add constraint FK_5jh2jf636mhuh77q4hwl1i2w0 
21:22:25,642 INFO  [stdout] (ServerService Thread Pool -- 13)         foreign key (usuario_cuenta) 
21:22:25,642 INFO  [stdout] (ServerService Thread Pool -- 13)         references Usuario (cuenta)
21:22:25,657 INFO  [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 50) HHH000230: Schema export complete
21:22:25,664 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 13) HHH000389: Unsuccessful: alter table Contacto add constraint FK_5jh2jf636mhuh77q4hwl1i2w0 foreign key (usuario_cuenta) references Usuario (cuenta)
21:22:25,665 ERROR [org.hibernate.tool.hbm2ddl.SchemaExport] (ServerService Thread Pool -- 13) Can't write; duplicate key in table '#sql-2f4_20'

貌似应用有2个hibernate的Thread，这些Thread都在做同样的SQL语句（比如创建同样的表等等……）

发生了什么事？

提前致谢

【问题讨论】：

在我们查看您的一些代码之前很难说什么。

标签： java multithreading hibernate jpa

【解决方案1】：

您的问题不在休眠状态。您的代码与编译后的代码不同步。尝试让它始终保持同步，或者创建一个新的工作区并从那里的仓库下载你的代码。

【讨论】：