mysql 排序问题
mysql 查询出一个数据列表 这个数据列表是分页的 比如说5个记录一页
<br />$page = $_REQUEST['page'];<br /><br />select * from user limit ($page-1)*5,5;<br />
然后查询的数组比如说为$user_list 然后循环这个user_list
<br />foreach($user_list as $k=>$v){<br /> // 然后根据某函数比如说 aa 计算出一个新的字段cc<br /> $user_list[$k]['cc'] = aa($v['id']);<br />}<br />
然后想按照cc这个字段排序user表 遇到的问题是 列表是分页的 第一页排序是正常 从小
到大排序 但是点击第二页又会出现从小到大排序 而不是已整体为依据 排序整个数据
cc 是经常变的字段,不能存到数据库 必须经由计算得出 请教一下大家有什么好的解决方法
------解决思路----------------------
使用create temporary table temp
创建一个临时表,然后把cc计算好后作为字段保存在temp中,然后再对临时表排序,分页。
------解决思路----------------------
你只对读取到的部分数据进行了计算,当然排序的效果就不是预期的了
如果你是需要按距离排序,那么可以这样做:
假定表中有 X、Y 字段分别保存有商家的经纬度
$x、$y 表示用户的经纬度
则有 select * from user ORDER BY abs($x-X), abs($y-Y) limit ($page-1)*5,5;

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