问题与“ManyToMany”关系Spring JPA [英] Issue with "ManyToMany" relationship Spring JPA
本文介绍了问题与“ManyToMany”关系Spring JPA的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我对Spring很陌生，所以很抱歉，如果这真的是一个非常愚蠢的问题，但我已经尝试了几乎所有的东西。我有用户和角色实体，他们之间有很多关系。如果我删除关系它工作得很好，否则我会得到错误。你能帮我一下吗？
Role类
import javax .persistence *。
import java.util.HashSet;
import java.util.Set;
@Entity
公共类角色{
私人长ID;
私人设定<使用者> users = new HashSet<>（）;
$ b公共角色（）{}
@Id
@GeneratedValue（strategy = GenerationType.AUTO）
@Column（name =id）
public Long getId（）{
return id;
}
public void setId（Long id）{
this.id = id;
}
@ManyToMany（mappedBy =roles）
public Set< User> getUsers（）{
返回用户;
}
public void setUsers（Set< User> users）{
this.users = users;
$ / code $ / pre
$ b $ User类 import javax.persistence。*;
import java.util.HashSet;
import java.util.Set;
@实体
公共类用户{
私人长ID;
私人设置<角色> roles = new HashSet<>（）;
public User（）{}
@Id
@GeneratedValue（strategy = GenerationType.AUTO）
@Column（name =id）
public Long getId（）{
return id;
}
public void setId（Long id）{
this.id = id;
$ b @ManyToMany
@JoinTable（name =user_roles，joinColumns = @JoinColumn（name =user_id，referencedColumnName =id），
inverseJoinColumns = @JoinColumn（name =role_id，referencedColumnName =id））
public Set< Role> getRoles（）{
返回角色;
}
public void setRoles（Set< Role> roles）{
this.roles = roles;
错误
org.springframework.beans.factory.BeanCreationException：在类路径资源[org / springframework / boot / autoconfigure / orm / jpa中定义名称'entityManagerFactory' /HibernateJpaAutoConfiguration.class]：调用init方法失败;嵌套异常是javax.persistence.PersistenceException：[PersistenceUnit：default]无法在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean中创建Hibernate SessionFactory
（AbstractAutowireCapableBeanFactory.java:1628）〜[spring-beans- 4.3.7.RELEASE.jar：4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:555）〜[spring-beans-4.3.7.RELEASE .jar：4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean（AbstractAutowireCapableBeanFactory.java:483）〜[spring-beans-4.3.7.RELEASE.jar：4.3。 7.RELEASE]
在org.springframework.beans.factory.support.AbstractBeanFactory $ 1.getObject（AbstractBeanFactory.java:306）〜[spring-beans-4.3.7.RELEASE.jar：4.3.7.RELEASE]
在org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegist ry.java:230）〜[spring-beans-4.3.7.RELEASE.jar：4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java:302 ）〜[spring-beans-4.3.7.RELEASE.jar：4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:197）〜[spring- beans-4.3.7.RELEASE.jar：4.3.7.RELEASE]
在org.springframework.context.support.AbstractApplicationContext.getBean（AbstractApplicationContext.java:1081）〜[spring-context-4.3.7.RELEASE .jar：4.3.7.RELEASE]
在org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization（AbstractApplicationContext.java:856）〜[spring-context-4.3.7.RELEASE.jar：4.3.7。
at org.springframework.context.support.AbstractApplicationContext.refresh（AbstractApplicationContext.java:542）〜[spring-context-4.3.7.RELEASE.jar：4.3.7.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContex t.refresh（EmbeddedWebApplicationContext.java:122）〜[spring-boot-1.5.2.RELEASE.jar：1.5.2.RELEASE]
at org.springframework.boot.SpringApplication.refresh（SpringApplication.java:737 ）[spring-boot-1.5.2.RELEASE.jar：1.5.2.RELEASE]
在org.springframework.boot.SpringApplication.refreshContext（SpringApplication.java:370）[spring-boot-1.5.2。 RELEASE.jar：1.5.2.RELEASE]
在org.springframework.boot.SpringApplication.run（SpringApplication.java:314）[spring-boot-1.5.2.RELEASE.jar：1.5.2.RELEASE]
在org.springframework.boot.SpringApplication.run（SpringApplication.java:1162）[spring-boot-1.5.2.RELEASE.jar：1.5.2.RELEASE]
在org.springframework.boot .SpringApplication.run（SpringApplication.java:1151）[spring-boot-1.5.2.RELEASE.jar：1.5.2.RELEASE]
at com.restaurant.AppConfig.main（AppConfig.java:14）[ main /：na]
导致：javax.persistence.PersistenceException：[PersistenceUnit：default]无法在org.hibernate中构建Hibernate SessionFactory
.jpa.boot.internal.EntityManagerFactoryBuilderImpl.persistenceException（EntityManagerFactoryBuilderImpl.java:954）〜[hibernate-entitymanager-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.jpa.boot。 internal.EntityManagerFactoryBuilderImpl.build（EntityManagerFactoryBuilderImpl.java:882）〜[hibernate-entitymanager-5.0.12.Final.jar：5.0.12.Final]
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory （SpringHibernateJpaPersistenceProvider.java:60）〜[spring-orm-4.3.7.RELEASE.jar：4.3.7.RELEASE]
在org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory（LocalContainerEntityManagerFactoryBean.java:353） 〜[spring-orm-4.3.7.RELEASE.jar：4.3.7.RELEASE]
在org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory（AbstractEntityManagerFactoryBean.java:370）〜[spring-orm-4.3 .7.RELEASE.jar：4.3.7.RELEASE]
在org.springframework.o rm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet（AbstractEntityManagerFactoryBean.java:359）〜[spring-orm-4.3.7.RELEASE.jar：4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory .invokeInitMethods（AbstractAutowireCapableBeanFactory.java:1687）〜[spring-beans-4.3.7.RELEASE.jar：4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean（AbstractAutowireCapableBeanFactory。 java：1624）〜[spring-beans-4.3.7.RELEASE.jar：4.3.7.RELEASE]
...省略16个常用框架
由org.hibernate.tool.schema引起。 spi.SchemaManagementException：无法执行对JDBC目标的架构管理[alter table user_roles add constraint FKrhfovtciq1l558cw6udg0h0d3 foreign key（role_id）references role（id）]
at org.hibernate.tool.schema.internal.TargetDatabaseImpl.accept（TargetDatabaseImpl .java：59）〜[hibernate-core-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.tool。 schema.internal.SchemaMigratorImpl.applySqlString（SchemaMigratorImpl.java:431）〜[hibernate-core-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl .applySqlStrings（SchemaMigratorImpl.java:420）〜[hibernate-core-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.applyForeignKeys（SchemaMigratorImpl。 java：386）〜[hibernate-core-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.doMigrationToTargets（SchemaMigratorImpl.java:214）〜 [hibernate-core-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.doMigration（SchemaMigratorImpl.java:60）〜[hibernate-core- 5.0.12.Final.jar：5.0.12.Final]
在org.hibernate.tool.hbm2ddl.SchemaUpdate.execute（SchemaUpdate.java:134）〜[hibernate-core-5.0.12.Final.jar ：5.0.12.Final]
在org.hibernate.tool.hbm2ddl.SchemaUpdate.execute（SchemaUpdate.java:101）〜[hibernate-core-5.0.1 2.Final.jar：5.0.12.Final]
at org.hibernate.internal.SessionFactoryImpl。< init>（SessionFactoryImpl.java:472）〜[hibernate-core-5.0.12.Final.jar： 5.0.12.Final]
在org.hibernate.boot.internal.SessionFactoryBuilderImpl.build（SessionFactoryBuilderImpl.java:444）〜[hibernate-core-5.0.12.Final.jar：5.0.12.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build（EntityManagerFactoryBuilderImpl.java:879）〜[hibernate-entitymanager-5.0.12.Final.jar：5.0.12.Final]
.. 22个常见的框架被忽略
引起：java.sql.SQLException：无法在com.mysql.jdbc.SQLError.createSQLException（SQLError.java:964）〜[mysql-connector- java-5.1.41.jar：5.1.41]
在com.mysql.jdbc.MysqlIO.checkErrorPacket（MysqlIO.java:3973）〜[mysql-connector-java-5.1.41.jar：5.1.41 ]
at com.mysql.jdbc.MysqlIO.checkErrorPacket（MysqlIO.java:3909）〜[mysql-connector-java-5.1.41.jar：5.1.41]
at com.mysql.jdbc .MysqlIO.sendC ommand（MysqlIO.java:2527）〜[mysql-connector-java-5.1.41.jar：5.1.41]
at com.mysql.jdbc.MysqlIO.sqlQueryDirect（MysqlIO.java:2680）〜[mysql -connector-java-5.1.41.jar：5.1.41]
at com.mysql.jdbc.ConnectionImpl.execSQL（ConnectionImpl.java:2497）〜[mysql-connector-java-5.1.41.jar： 5.1.41]
at com.mysql.jdbc.StatementImpl.executeUpdateInternal（StatementImpl.java:1540）〜[mysql-connector-java-5.1.41.jar：5.1.41]
at com。 mysql.jdbc.StatementImpl.executeLargeUpdate（StatementImpl.java:2595）〜[mysql-connector-java-5.1.41.jar：5.1.41]
at com.mysql.jdbc.StatementImpl.executeUpdate（StatementImpl.java ：1468）〜[mysql-connector-java-5.1.41.jar：5.1.41]
在org.hibernate.tool.schema.internal.TargetDatabaseImpl.accept（TargetDatabaseImpl.java:56）〜[hibernate- core-5.0.12.Final.jar：5.0.12.Final]
... 32个常见框架省略
：bootRun失败
解决方案考虑将其设为单向。在正常情况下，您只需要知道给定用户具有哪些角色。所以，最好的解决方法是从你的角色类中完全移除getUsers（）。
为了让它运行起来，请在关系的两边使用连接表。试试这个;
Role.java;
@ManyToMany
@JoinTable（name =user_roles，
joinColumns = @JoinColumn（name =role_id），
inverseJoinColumns = @JoinColumn（name =user_id））
public Set< User> getUsers（）
User.java
@ManyToMany
@JoinTable（name =user_roles，
joinColumns = @ JoinColumn（name =user_id），
inverseJoinColumns = @ JoinColumn =role_id））
public Set< Role> getRoles（）{
也尝试添加到application.properties中，但仅用于测试！ / p>
spring.jpa.hibernate.ddl-auto =创建 - 删除
以防万一，从mysql我也会尝试
drop数据库你的数据库名称;
创建数据库your-database-name;
I'm new to Spring so sorry if this turns out to be a really dumb question, but I've tried almost everything. I have User and Role entities and there's a many to many relationship between them. If i remove the relationship it works just fine, otherwise I get errors. Could you help me out?
The Role class
import javax.persistence.*;
import java.util.HashSet;
import java.util.Set;
@Entity
public class Role {
private Long id;
private Set<User> users = new HashSet<>();
public Role(){}
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "id")
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
@ManyToMany(mappedBy = "roles")
public Set<User> getUsers() {
return users;
}
public void setUsers(Set<User> users) {
this.users = users;
}
}
The User class
import javax.persistence.*;
import java.util.HashSet;
import java.util.Set;
@Entity
public class User {
private Long id;
private Set<Role> roles = new HashSet<>();
public User(){}
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
@Column(name = "id")
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
@ManyToMany
@JoinTable(name = "user_roles", joinColumns = @JoinColumn(name = "user_id",referencedColumnName = "id"),
inverseJoinColumns = @JoinColumn(name = "role_id",referencedColumnName = "id"))
public Set<Role> getRoles() {
return roles;
}
public void setRoles(Set<Role> roles) {
this.roles = roles;
}
}
The Errors
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in class path resource [org/springframework/boot/autoconfigure/orm/jpa/HibernateJpaAutoConfiguration.class]: Invocation of init method failed; nested exception is javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1628) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1081) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:856) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542) ~[spring-context-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:737) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:370) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:314) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151) [spring-boot-1.5.2.RELEASE.jar:1.5.2.RELEASE]
at com.restaurant.AppConfig.main(AppConfig.java:14) [main/:na]
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: default] Unable to build Hibernate SessionFactory
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.persistenceException(EntityManagerFactoryBuilderImpl.java:954) ~[hibernate-entitymanager-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:882) ~[hibernate-entitymanager-5.0.12.Final.jar:5.0.12.Final]
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:60) ~[spring-orm-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:353) ~[spring-orm-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:370) ~[spring-orm-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:359) ~[spring-orm-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624) ~[spring-beans-4.3.7.RELEASE.jar:4.3.7.RELEASE]
... 16 common frames omitted
Caused by: org.hibernate.tool.schema.spi.SchemaManagementException: Unable to execute schema management to JDBC target [alter table user_roles add constraint FKrhfovtciq1l558cw6udg0h0d3 foreign key (role_id) references role (id)]
at org.hibernate.tool.schema.internal.TargetDatabaseImpl.accept(TargetDatabaseImpl.java:59) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.applySqlString(SchemaMigratorImpl.java:431) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.applySqlStrings(SchemaMigratorImpl.java:420) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.applyForeignKeys(SchemaMigratorImpl.java:386) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.doMigrationToTargets(SchemaMigratorImpl.java:214) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.schema.internal.SchemaMigratorImpl.doMigration(SchemaMigratorImpl.java:60) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:134) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.tool.hbm2ddl.SchemaUpdate.execute(SchemaUpdate.java:101) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:472) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:444) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:879) ~[hibernate-entitymanager-5.0.12.Final.jar:5.0.12.Final]
... 22 common frames omitted
Caused by: java.sql.SQLException: Cannot add foreign key constraint
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3973) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3909) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2527) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2680) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2497) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.StatementImpl.executeUpdateInternal(StatementImpl.java:1540) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.StatementImpl.executeLargeUpdate(StatementImpl.java:2595) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at com.mysql.jdbc.StatementImpl.executeUpdate(StatementImpl.java:1468) ~[mysql-connector-java-5.1.41.jar:5.1.41]
at org.hibernate.tool.schema.internal.TargetDatabaseImpl.accept(TargetDatabaseImpl.java:56) ~[hibernate-core-5.0.12.Final.jar:5.0.12.Final]
... 32 common frames omitted
:bootRun FAILED
解决方案 Consider making this uni-directional. Under normal circumstances, you only need to know which roles a given user has. So, best fix would be to remove getUsers() from your role class completely.
For reference to get it running, use a join table on both sides of the relationship. Give this a try;
Role.java;
@ManyToMany
@JoinTable(name = "user_roles",
joinColumns = @JoinColumn(name="role_id"),
inverseJoinColumns = @JoinColumn(name="user_id"))
public Set<User> getUsers ()
User.java
@ManyToMany
@JoinTable(name="user_roles",
joinColumns=@JoinColumn(name="user_id"),
inverseJoinColumns=@JoinColumn(name="role_id"))
public Set<Role> getRoles() {
[edit] Also try adding this to application.properties but ONLY for testing!
spring.jpa.hibernate.ddl-auto=create-drop
Just in case, from mysql I would also try
drop database your-database-name;
create database your-database-name;
这篇关于问题与“ManyToMany”关系Spring JPA的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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