所以,我有两个表是一对多的关系,当我尝试登录时,我收到一些关于user0_id字段的错误.问题是我只在错误被触发时发送用户名和密码,所以我不确定是什么导致它.我已经阅读了关于这个问题的类似帖子,它似乎与实体和表之间的映射有关.所以,这是我的实体.
@Entity
@Table(name="user")
public class User {
@Id
@Column(name="id")
@GeneratedValue
private int id;
@Column(name="email")
private String email;
@Column(name="username")
private String username;
@Column(name="password")
private String password;
@Column(name="authority")
private String authority;
@OneToMany(cascade={CascadeType.ALL})
@JoinColumn(name="id")
private List<Post> posts;
...
}
另一个:
@Entity
@Table(name="post")
public class Post {
@Id
@Column(name="id")
@GeneratedValue
private int id;
@Column(name="title")
private String title;
@Column(name="content")
private String content;
@ManyToOne
@JoinColumn(name="userId", insertable=false, updatable=false, nullable=false)
private User user;
...
}
有人可以给我一个关于可能导致这种情况的指针吗?因为我没有看到任何错误,列和表之间的名称是相同的.
表:
post
1 id int(11)
2 title varchar(45)
3 content longtext
4 userId int(11)
user
1 id int(11)
2 email varchar(45)
3 authority varchar(45)
4 username varchar(45)
5 password varchar(45)
错误:
ERROR: Unknown column 'user0_.id' in 'field list'
org.hibernate.exception.SQLGrammarException: could not extract ResultSet
at org.hibernate.exception.internal.SQLExceptionTypeDelegate.convert(SQLExceptionTypeDelegate.java:80)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:49)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:126)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:112)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:91)
at org.hibernate.loader.Loader.getResultSet(Loader.java:2066)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1863)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1839)
at org.hibernate.loader.Loader.doQuery(Loader.java:910)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:355)
at org.hibernate.loader.Loader.doList(Loader.java:2554)
at org.hibernate.loader.Loader.doList(Loader.java:2540)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2370)
at org.hibernate.loader.Loader.list(Loader.java:2365)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:497)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:387)
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:236)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1264)
at org.hibernate.internal.QueryImpl.list(QueryImpl.java:103)
at com.personal.services.LoginService.login(LoginService.java:24)
at com.personal.controllers.HomeController.login(HomeController.java:54)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:222)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:814)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:737)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:969)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:871)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:648)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:845)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:212)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:141)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:521)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1096)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:674)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown column 'user0_.id' in 'field list'
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
at com.mysql.jdbc.Util.getInstance(Util.java:387)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:939)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3878)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3814)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2478)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2625)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2551)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1861)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1962)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:82)
... 54 more
最佳答案 您的映射确实不正确.
@OneToMany(cascade={CascadeType.ALL})
@JoinColumn(name="id")
private List<Post> posts;
这是没有意义的.您是说帖子通过使用post.id列引用用户.这不可能是正确的,因为id如果是post的主键.
它也是不正确的,因为你想要一个双向的OneToMany关联,因此单方必须是关联的反面.
这是正确的映射:
@OneToMany(mappedBy="user", cascade={CascadeType.ALL})
private List<Post> posts;
在邮报中:
@ManyToOne
@JoinColumn(name="userId", nullable=false)
private User user;