<insert id="insertProductRelation" parameterType="java.util.List">
<selectKey resultType="java.lang.Integer" order="BEFORE" keyProperty="relationId">
select seq_relation_goods_attribute.nextval as relationId from dual
</selectKey>
insert into t_relation_goods_attribute(relation_id,...)
values
<foreach collection="list" item="obj" index="index" separator=",">
(#{obj.relationId,jdbcType=NUMERIC},...)
</foreach>
不支持oracle数据库插入！！