A query was run and no Result Maps were found for the Mapped Statement 'user.insertUser!selectKey'. It's likely that neither a Result Type nor a Result Map was specified.

使用mybatis时出现异常问题：

有如下的错误

 Error querying database.  Cause: org.apache.ibatis.executor.ExecutorException: A query was run and no Result Maps were found for the Mapped Statement 'user.insertUser!selectKey'.  It's likely that neither a Result Type nor a Result Map was specified.

这个是使用MyBatis最常见的一种错误，从其描述来看是user.insertUser!selectKey这个Statement没有Result Type或Result Map。下面是我的配置文件的statement：

 <insert id="insertUser" parameterType="com.luchao.mybatis.first.po.User">
         <selectKey keyProperty="id" order="AFTER" >
             select LAST_INSERT_ID()
         </selectKey>
         insert into user(username,birthday,sex,address) value (#{username},#{birthday},#{sex},#{address});
 </insert>

可以看出主要是<selectKey>没有resultType所致的。

mybatis中不管什么查询，都必须返回resultType或者resultMap的值，否则就会报错的。