mybatis批量更新foreach里的list是怎么来的，哪儿定义的，求解？

<update id="batchUpdateStudent" parameterType="List">
UPDATE STUDENT SET name = "5566" WHERE id IN
<foreach collection="list" item="item" index="index" open="(" separator="," close=")" >
#{item}
</foreach>
</update>

相关了解……