iBtais 多重嵌套循环

iBatis支持集合循环， 但是如何做到双重循环， 请见下例子

例子描述：

需要去三张结构相同的表中获取信息, 需要将信息拼合去重后返回

入参数据类型： Map<String,Object>,   regions  = List<OrderRegionNum>

class OrderRegionNums{
String regionSchema
String regionCode
List<Integer> orderNums
}

注意的是在标签中的property属性中使用时：不需要加 $或者#  直接regions[].orderNums
<select id="selectOrderNumListByRegionCodeByListOrderNum" resultMap="orderNumInfo" parameterClass="java.util.HashMap">

<dynamic>

<iterate property="regions" conjunction="UNION">

　　select distinct(r.ID),r.ORD_NR,r.ORD_RGN_CD

　　from $regions[].regionSchema$.table

where

　　r.EXCH_SRVCR_QT > 0

　　and r.ORD_RGN_CD = #regions[].regionCode#

　　and r.ORD_NR in

　　　　<iterate property="regions[].orderNums" open="(" close=")" conjunction="," >

　　　　　　#regions[].orderNums[]#

　　　　</iterate>

　　</iterate>

</dynamic>

</select>

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<isNotEmpty prepend="and" property="marketShopAuthFlatAreaDtos">
    <iterate property="marketShopAuthFlatAreaDtos" conjunction="or">
        project_id in
        <iterate conjunction=',' property="marketShopAuthFlatAreaDtos[].projectIds" open="(" close=")">
            #marketShopAuthFlatAreaDtos[].projectIds[]#</iterate>
        AND
        (
        1!=1
        <isNotEmpty prepend="or" property="marketShopAuthFlatAreaDtos[].provinceNodes" >
            shop_address_province in
            <iterate conjunction=',' property="marketShopAuthFlatAreaDtos[].provinceNodes" open="(" close=")">
                #marketShopAuthFlatAreaDtos[].provinceNodes[].nodeCode#</iterate>

        </isNotEmpty>
        <isNotEmpty prepend="or" property="marketShopAuthFlatAreaDtos[].cityNodes">
            shop_address_city in
            <iterate conjunction=',' property="marketShopAuthFlatAreaDtos[].cityNodes" open="(" close=")">
                #marketShopAuthFlatAreaDtos[].cityNodes[].nodeCode#</iterate>

        </isNotEmpty>

        <isNotEmpty prepend="or" property="marketShopAuthFlatAreaDtos[].countyNodes">

            shop_address_country in
            <iterate conjunction=',' property="marketShopAuthFlatAreaDtos[].countyNodes" open="(" close=")">
                #marketShopAuthFlatAreaDtos[].countyNodes[].nodeCode#</iterate>

        </isNotEmpty>
        <isNotEmpty prepend="or" property="marketShopAuthFlatAreaDtos[].townNodes">

            shop_address_street in
            <iterate conjunction=',' property="marketShopAuthFlatAreaDtos[].townNodes" open="(" close=")">
                #marketShopAuthFlatAreaDtos[].townNodes[].nodeCode#</iterate>

        </isNotEmpty>
        )
    </iterate>

</isNotEmpty>

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<sql id="Example_Where_Clause">
  <where>
    <foreach collection="oredCriteria" item="criteria" separator="or">
      <if test="criteria.valid">
        <trim prefix="(" prefixOverrides="and" suffix=")">
          <foreach collection="criteria.criteria" item="criterion">
            <choose>
              <when test="criterion.noValue">
                and ${criterion.condition}
              </when>
              <when test="criterion.singleValue">
                and ${criterion.condition} #{criterion.value}
              </when>
              <when test="criterion.betweenValue">
                and ${criterion.condition} #{criterion.value} and #{criterion.secondValue}
              </when>
              <when test="criterion.listValue">
                and ${criterion.condition}
                <foreach close=")" collection="criterion.value" item="listItem" open="(" separator=",">
                  #{listItem}
                </foreach>
              </when>
            </choose>
          </foreach>
        </trim>
      </if>
    </foreach>
  </where>
</sql>