关于mybatis中懒加载的中问题，拜托各位大神了，我检查了好几遍

Question

这个是maper配置：







select * from table_many

  <select id="findLazyOne" parameterType="java.lang.String"  resultType="tableOne" >
    select * from table_one t where t.m_id=#{value}
  </select>

        这个是调用方法：
        static TableManyMapper mapper=null;
  public static void main(String[] args) throws Exception {

      String resource="mybatis.xml";
      InputStream input=Resources.getResourceAsStream(resource);    
      SqlSessionFactory factory=new SqlSessionFactoryBuilder().build(input);
      SqlSession sqlSession = factory.openSession();
         mapper=sqlSession.getMapper(TableManyMapper.class);

         findMany();

        sqlSession.commit();
}     
     public static void findMany(){ 
        List<TableMany> list= mapper.findMany();
        for (TableMany tableMany : list) {
            System.out.println(tableMany.getM_id()+"::"+tableMany.getM_name());
            System.out.println(".......");
                List<TableOne> oneList=tableMany.getOneList();
                for (TableOne tableOne : oneList) {
                    System.out.println(tableOne.getO_id()+"::"+tableOne.getO_name());
                }

        }
     }

        这个是报错：
        32acceba-7d07-11e7-acb7-14dda920ec0e::多的一方1

.......
Exception in thread "main" org.apache.ibatis.executor.ExecutorException: Statement returned more than one row, where no more than one was expected.
at org.apache.ibatis.executor.ResultExtractor.extractObjectFromList(ResultExtractor.java:50)
at org.apache.ibatis.executor.loader.ResultLoader.loadResult(ResultLoader.java:71)
at org.apache.ibatis.executor.loader.ResultLoaderMap$LoadPair.load(ResultLoaderMap.java:207)
at org.apache.ibatis.executor.loader.ResultLoaderMap$LoadPair.load(ResultLoaderMap.java:172)
at org.apache.ibatis.executor.loader.ResultLoaderMap.load(ResultLoaderMap.java:80)
at org.apache.ibatis.executor.loader.cglib.CglibProxyFactory$EnhancedResultObjectProxyImpl.intercept(CglibProxyFactory.java:147)
at com.mybatis.pojo.TableMany$$EnhancerByCGLIB$$49d2b6d7.getOneList()
at com.mybatis.test.ManayToOne.findMany(ManayToOne.java:62)
at com.mybatis.test.ManayToOne.main(ManayToOne.java:28)

Answer 1

看报错信息是你的方法本来要求查询的语句只能返回一行数据，但是在真正查询的时候出现了两条或更过，所以报错了。看看数据库m_id会不会有重复的？。。。。。。。。是不是楼主代码有部分没贴？