1、Dao层

int insertAll(List<OrEntity> list);

2、mapper.xml文件

 <insert id="insertAll" parameterType="java.util.List" useGeneratedKeys="false">
         INSERT INTO a
         (
             ID,
             NAME,
             EMAIL,
             AGE
         )
         <foreach item="item" index="index" collection="list" separator="union all">
         (
             SELECT
                 #{item.id},
                 #{item.name},
                 #{item.email},
                 #{item.age}
             FROM DUAL
         )
         </foreach>
    </insert>