mybatis的resultMap中字段重名处理

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问题

在写mybatis的关联查询时，resultMap中如果两个对象有相同的属性。查询出来的结果内层的对象的属性会被外层对象属性覆盖，导致内层list数据出错。

resultMap结构如下：

<resultMap id="DetailResultMap" type="com.tchirk.itsm.ca.domain.System"><result column="object_version_number" jdbcType="BIGINT" property="objectVersionNumber"/><result column="created_by" jdbcType="BIGINT" property="createdBy"/><result column="creation_date" jdbcType="TIMESTAMP" property="creationDate"/><collection property="moduleList" ofType="com.tchirk.itsm.ca.domain.Module"><result column="object_version_number" jdbcType="BIGINT" property="objectVersionNumber"/><result column="created_by" jdbcType="BIGINT" property="createdBy"/><result column="creation_date" jdbcType="TIMESTAMP" property="creationDate"/></collection></resultMap>

查询关联对象的SELECT语句如下

<select id="selectSystem" resultMap="DetailResultMap" resultType="com.tchirk.itsm.ca.domain.System">SELECTs1.object_version_number,s1.last_updated_by,s1.last_update_date,m1.object_version_number,m1.last_updated_by,m1.last_update_dateFROM itsm_system s1left join itsm_module m1on m1.system_id=s1.system_id
</select>

解决

将关联对象的相同属性名重命名,然后在resultMap中将column属性修改为查询语句中重命名的名字。

<select id="selectSystem" resultMap="DetailResultMap" resultType="com.tchirk.itsm.ca.domain.System">SELECTs1.object_version_number,s1.last_updated_by,s1.last_update_date,m1.object_version_number m1_object_version_number,m1.last_updated_by m1_last_updated_by,m1.last_update_date m1_last_update_dateFROM itsm_system s1left join itsm_module m1on m1.system_id=s1.system_id
</select>

    <resultMap id="DetailResultMap" type="com.tchirk.itsm.ca.domain.System"><result column="object_version_number" jdbcType="BIGINT" property="objectVersionNumber"/><result column="created_by" jdbcType="BIGINT" property="createdBy"/><result column="creation_date" jdbcType="TIMESTAMP" property="creationDate"/><collection property="moduleList" ofType="com.tchirk.itsm.ca.domain.Module"><result column="m1_object_version_number" jdbcType="BIGINT" property="objectVersionNumber"/><result column="m1_created_by" jdbcType="BIGINT" property="createdBy"/><result column="m1_creation_date" jdbcType="TIMESTAMP" property="creationDate"/></collection></resultMap>