Question

MyBatis 3 - Spring

我想插入项目列表，并且每个项目ID必须从“TVA_UPSELLADMIN_CHANNEL_SEQ.nextVal”生成，但我得到.xml验证错误，您不能在“foreach”内部子子“selectKey”。

<insert id="insertServiceMappings" parameterType="java.util.List">

INSERT  
<foreach collection="list" item="channel" index="index" >

<selectKey keyProperty="id" resultType="long" order="BEFORE">
            SELECT TVA_UPSELLADMIN_CHANNEL_SEQ.nextVal from dual
        </selectKey>

into tva_upselladmin_channel (id,source_id, service_id, name) values (#{id}, #{channel.sourceId}, #{channel.serviceId}, #{channel.name})
</foreach>
</insert>

Answer 1

MyBatis的当前版本（或任何相关人员）不允许在<selectKey>标记内使用<forEach>。它是否仅用于遍历列表。

<foreach>标记的MyBatis dtd验证部分如下：

<!ELEMENT foreach (#PCDATA | include | trim | where | set | foreach | choose | if | bind)*>
<!ATTLIST foreach
collection CDATA #REQUIRED
item CDATA #IMPLIED
index CDATA #IMPLIED
open CDATA #IMPLIED
close CDATA #IMPLIED
separator CDATA #IMPLIED
>

因此，为了解决您的问题，您必须遍历列表设置所有ID，并在XML上添加额外的select定义。这就像是：

<select id="nextvalKey" resultType="java.lang.Integer">
     SELECT TVA_UPSELLADMIN_CHANNEL_SEQ.nextVal from dual
</select>

您的插入部分如下：

<insert id="insertServiceMappings" parameterType="java.util.List">
    <foreach collection="list" item="channel" index="index" >
        INSERT INTO tva_upselladmin_channel (id,source_id, service_id, name)
              VALUES ( #{id}, #{channel.sourceId}, #{channel.serviceId}, #{channel.name});
    </foreach>
</insert>

不要忘记插入命令后的;因为ORACLE不支持多个值插入，例如insert ... values (1,'bla'), (2, 'ble'), (3, 'bli');）

所以第二部分是在你的实现中有一个方法来为列表中的项设置每个id。它会是这样的：

  public void someMethodInsertList(List<SomeObject> list){
       //normally I do an implementation that allows me to use
       //sqlSessionTemplate from mybatis through an extended class 
       for ( SomeObject obj : list ){
           obj.setId( getSqlSessionTemplate.selectOne( 'nextvalKey' ) );
       }
       getSqlSessionTemplate.insert( 'insertServiceMappings', list );
  }

希望有所帮助

Answer 2

我找到另一种解决方案如下，它对我有用！

 <insert id="insertServiceMappings" parameterType="java.util.List" useGeneratedKeys="true">
         <selectKey keyProperty="id" resultType="java.lang.Long" order="BEFORE">
                SELECT TVA_UPSELLADMIN_CHANNEL_SEQ.nextVal as id FROM DUAL
         </selectKey>    
         INSERT INTO
         tva_upselladmin_channel (id,source_id, service_id, name)
         SELECT TVA_UPSELLADMIN_CHANNEL_SEQ.nextVal, A.* from (
         <foreach collection="list" item="channel" index="index" separator="union all">
         SELECT 
           #{channel.sourceId} as source_id,
           #{channel.serviceId} as service_id,
           #{channel.name}) as name
         FROM DUAL
         </foreach> ) A
    </insert>

在foreach里面的mybatis 3 selectkey

2 个答案: