在seckill的reduceNumber方法参数问题
<update id="reduceNumber" > -- 具体sql UPDATE seckill set number =number-1; where seckill_id = #{seckillId} and start_time <![CDATA[<=]]> #{killTime} and end_time >= #{killTime} and number > 0; </update> 为什么可以自动识别#{seckillId} ,#{killTime} ?