利用hibernate向数据库表中插入数据,插入不了

Question

小弟用hibernate向数据库表中插入数据,但是产生错误.java.sql.SQLException: Field 'wid' doesn't have a default value
但是我的wid字段为主键,不需要默认值 希望高手指点严重: Servlet.service() for servlet jsp threw exception
java.sql.SQLException: Field 'wid' doesn't have a default value
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:2847)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:1531)
at com.mysql.jdbc.ServerPreparedStatement.serverExecute(ServerPreparedStatement.java:1347)
at com.mysql.jdbc.ServerPreparedStatement.executeInternal(ServerPreparedStatement.java:958)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1957)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1880)
at com.mysql.jdbc.PreparedStatement.executeUpdate(PreparedStatement.java:1741)
at org.hibernate.id.IdentityGenerator$GetGeneratedKeysDelegate.executeAndExtract(IdentityGenerator.java:73)
at org.hibernate.id.insert.AbstractReturningDelegate.performInsert(AbstractReturningDelegate.java:33)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2158)
at org.hibernate.persister.entity.AbstractEntityPersister.insert(AbstractEntityPersister.java:2638)
at org.hibernate.action.EntityIdentityInsertAction.execute(EntityIdentityInsertAction.java:48)
at org.hibernate.engine.ActionQueue.execute(ActionQueue.java:250)
at org.hibernate.event.def.AbstractSaveEventListener.performSaveOrReplicate(AbstractSaveEventListener.java:298)
at org.hibernate.event.def.AbstractSaveEventListener.performSave(AbstractSaveEventListener.java:181)
at org.hibernate.event.def.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:107)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:187)
at org.hibernate.event.def.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:33)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:172)
at org.hibernate.event.def.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:27)
at org.hibernate.event.def.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:70)
at org.hibernate.impl.SessionImpl.fireSave(SessionImpl.java:535)
at org.hibernate.impl.SessionImpl.save(SessionImpl.java:523)
at org.hibernate.impl.SessionImpl.save(SessionImpl.java:519)
at myHibernate.WarehouseDAO.save(WarehouseDAO.java:39)
at org.apache.jsp.admin.addwarehousedo_jsp._jspService(addwarehousedo_jsp.java:74)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:393)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:266)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:261)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:581)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
at java.lang.Thread.run(Thread.java:619)

Answer 1

你要将 wid声明为@Id，即主键，同时要指定主键生成策略，如@Generated(type=GenerateType.AUTO)， 这样就能自动插入id了

Answer 2

wid我设置的是主键,主键策略如下
<id name="wid" type="java.lang.String">
            <column name="wid" length="4" />
            <generator class="native" />
</id>
是不是因为数据类型的原因?

Answer 3

wid我设置的是主键,主键策略如下
<id name="wid" type="java.lang.String">
  <column name="wid" length="4" />
  <generator class="native" />
</id>
是不是因为数据类型的原因?

Answer 4

 <generator class="native" />
这个是根据你数据库中的主键生成方式决定的，你看看你数据库设主键生成策略了没

Answer 5

而且自增长的怎么用string呢 应该用数值类型 long或int啊

Answer 6

wid我设置的是主键,主键策略如下
<id name="wid" type="java.lang.String">
  <column name="wid" length="4" />
  <generator class="native" />
</id>
是不是因为数据类型的原因?

Answer 7

一。将type="java.lang.String">修改java.lang.Integer
二。查一下你数据库中wid自段设自增没有

Answer 8

知道什么原因了 wid不是整形 设置成char了

Answer 9

<generator class="" />去了native
并且每次要给主键赋值