ibatis三表级联查询？？


  <!-- 广告组ResultMap -->
<resultMap id="googleAdGroupResult" class="com.tq365.vo.GoogleAdGroup">
<result property="adGroupId" column="adGroupId"></result>
<result property="googleAdGroupId" column="googleAdGroupId"></result>
<result property="campaignId" column="campaignId"></result>
<result property="kwMaxCPCContent" column="kwMaxCPCContent"></result>
<result property="kwMaxCPC" column="kwMaxCPC"></result>
<result property="siteMaxCPC" column="siteMaxCPC"></result>
<result property="adGroupName" column="adGroupName"></result>
<result property="status" column="status"></result>
<result property="syncTimestamp" column="syncTimestamp"></result>
<result property="syncStatus" column="syncStatus"></result>
<result property="syncMessage" column="syncMessage"></result>
<result property="updateTimestamp" column="updateTimestamp"></result>
<result property="adGroupInfoList" column="googleAdGroupId" select="findAdGroupInfosByAdGroupId"></result>
</resultMap>
<!-- 广告组统计信息  -->
<resultMap id="adGroupInfoResult" class="com.tq365.vo.AdGroupInfo">
    <result property="adGroupInfoId" column="adGroupInfoId"></result>
    <result property="googleAdGroupId" column="googleAdGroupId"></result>
    <result property="clicks" column="clicks"></result>
    <result property="impressions" column="impressions"></result>
    <result property="clicksRate" column="clicksRate"></result>
    <result property="costPerClick" column="costPerClick"></result>
    <result property="cost" column="cost"></result>
    <result property="averagePosition" column="averagePosition"></result>
    <result property="conversions" column="conversions"></result>
    <result property="costMConversions" column="costMConversions"></result>
    <result property="conversionsRate" column="conversionsRate"></result>
    <result property="googleAdGroup" column="googleAdGroupId" select="findAdGroupByAdGroupId"></result>
    <result property="insertTime" column="insertTime"></result>
</resultMap>
<resultMap id="googleCampaignsResult" class="com.tq365.vo.GoogleCampaigns">
<result property="campaignId" column="campaignId"></result>
<result property="googleCampaignId" column="googleCampaignId"></result>
<result property="accountId" column="accountId"></result>
<result property="bidCeiling" column="bidCeiling"></result>
<result property="enabled" column="enabled"></result>
<result property="takeOnOptimizedBids" column="takeOnOptimizedBids"></result>
<result property="optimizeAdServing" column="optimizeAdServing"></result>
<result property="startDay" column="startDay"></result>
<result property="endDay" column="endDay"></result>
<result property="name" column="name"></result>
<result property="languageTargets" column="languageTargets"></result>
<result property="status" column="status"></result>
<result property="geoTargetAll" column="geoTargetAll"></result>
<result property="noEnd" column="noEnd"></result>
<result property="networkGoogleSearch" column="networkGoogleSearch"></result>
<result property="networkSerarch" column="networkSerarch"></result>
<result property="networkContent" column="networkContent"></result>
<result property="syncTimestamp" column="syncTimestamp"></result>
<result property="syncStatus" column="syncStatus"></result>
<result property="syncMessage" column="syncMessage"></result>
<result property="updateTimestamp" column="updateTimestamp"></result>
<result property="budgetAmount" column="budgetAmount"></result>
<result property="budgetOptimizerEnable" column="budgetOptimizerEnable"></result>
<result property="campaignsinfoList" column="googleCampaignId"
select="campaignInfo.findByCampID"></result>
<result property="languageList" column="googleCampaignId" select="findLanguagesByCampId"></result>
</resultMap>GoogleAdGroup与AdGroupInfo是一对多的关系,
GoogleCampaign与GoogleAdGroup是一对多的关系
单一的，从AdGroupInfo可以查到GoogleAdGroup，从GoogleAdGroup也可以查到GoogleCampaign
但是为什么从AdGroupInfo直接查GoogleCampaign却查不到了
????