php做一个排名,根据时间排名,图中是按时间倒序排的,排队字段需要按时间正序排。
正确的排队顺序与序号反过来了5.4.3.2.1
回复讨论(解决方案)
我是掌握魔法的大师!
不是order by time就行了么
如果按id 逆序排可以这样写
select * from table order by id desc;
不是order by time就行了么
这个方法是可以,但是前面的序号是按 desc,而后面的排队是按asc,所以纠结呀。老板太挑剔了
你的 排队 列并没有数据
order by 字段
desc or asc
升序 desc
降序 asc
你的 排队 列并没有数据
恩,没有数据,序号列是$key,就是按降序排的。排序列需要按升序排,sql语句只能排一次。所以现在正纠结呢。初步打算是增加个字段,然后写一条循环语句,把排名写到这个字段里。不停地循环id,这样每条数据就有了排序字段的值了。可是不会根据ID循环
那你排名的依据是什么呢?
那你排名的依据是什么呢?
排名的依据是时间升序,而序号的依据是时间降序。所以两个冲突了
你的序号是输出时 php 代码产生的
那么你的排名就是 总数-序号
序号 排名1 52 43 34 2 5 1
你的序号是输出时 php 代码产生的
那么你的排名就是 总数-序号
序号 排名1 52 43 34 2 5 1
太对了,我就是想要这种效果。怎么做出来的?具体帮我说说吧,我不明白
取得查询结果的总记录数不是很难吧?
那么
echo '序号'.$i.' 排名' . ($count-$i);
$i++;
不就行了?

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