<update id="updateByList">update 表名<trim prefix="set" suffixOverrides=","><trim prefix="数据库字段名=case" suffix="end," ><foreach collection="list" item="i" index="index">when id=#{i.id} then #{i.对应参数实体属性名}</foreach></trim><trim prefix="数据库字段名=case" suffix="end," ><foreach collection="list" item="i" index="index">when id=#{i.id} then #{i.对应参数实体属性名}</foreach></trim></trim>where<foreach collection="list" separator="or" item="i" index="index" >id=#{i.id}</foreach>
</update>

list 为所需更新列表入参名称

void updateByList(@Param("list") List<实体名称> list);