MyBatis，集合的嵌套結果爲空

Question

我在MyBatis網站中創建一個具有嵌套集合的映射器，當我執行select操作時，我的對象（Provider）返回，但其中的集合（ ProviderParameter）是空的，當我轉到數據庫工具並應用相同的查詢時，我得到預期的結果（集合也返回）。

這裏是我的映射：

<resultMap id="Provider" type="xxx.Provider"> 
     <result column="idProvider" property="idProvider"/> 
     <result column="providerType" property="providerType"/> 
     <result column="username" property="username"/> 
     <result column="password" property="password"/> 
     <result column="licenceInformation" property="licenseInformation"/> 
     <collection property="parameters" ofType="xxx.ProviderParameter"> 
      <result column="idProviderParameter" property="idProviderParameter"/> 
      <result column="name" property="name"/> 
      <result column="value" property="value"/> 
     </collection> 
    </resultMap> 

和選擇：

<select id="getProviderById" resultType="xxx.Provider"> 
    select P.idProvider   as idProvider 
      ,P.providerType  as providerType 
      ,P.username   as username 
      ,P.password   as password 
      ,P.licenceInformation as licenceInformation 
      ,PP.idProviderParameter as idProviderParameter 
      ,PP.name    as name 
      ,PP.value    as value 
    from [dbo].[msg_Provider] AS P 
    left outer join [dbo].[msg_ProviderParameter] AS PP on P.idProvider = PP.idProvider  
    where P.idProvider = #{idProvider} 
</select> 

Answer 1

我的問題是，在選擇我把與resultType而不是resultMap，但

所以選擇應該是如：

<select id="getProviderById" resultMap="Provider"> 
    select P.idProvider   as idProvider 
      ,P.providerType  as providerType 
      ,P.username   as username 
      ,P.password   as password 
      ,P.licenceInformation as licenceInformation 
      ,PP.idProviderParameter as idProviderParameter 
      ,PP.name    as name 
      ,PP.value    as value 
    from [dbo].[msg_Provider] AS P 
    left outer join [dbo].[msg_ProviderParameter] AS PP on P.idProvider = PP.idProvider  
    where P.idProvider = #{idProvider} 
</select>