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
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然后查询的数组比如说为$user_list 然后循环这个user_list
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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
回复讨论(解决方案)
可以在查询的时候把你的计算公式aa嵌套进语句中算出CC(如果aa不太复杂的话) 然后直接按CC排序即可
可以在查询的时候把你的计算公式aa嵌套进语句中算出CC(如果aa不太复杂的话) 然后直接按CC排序即可
但是比如说我写的这个sql distance的值就计算不出来1 |
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那应该怎么实现像这样的msyql自定义函数 aa(变量1,变量2,表字段1,表字段2)
那应该怎么实现像这样的msyql自定义函数 aa(变量1,变量2,表字段1,表字段2)
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http://www.baidu.com/s?wd=mysql%20%E8%87%AA%E5%AE%9A%E4%B9%89%E5%87%BD%E6%95%B0&rsv_spt=1&issp=1&f=8&rsv_bp=0&ie=utf-8&tn=baiduhome_pg&rsv_enter=1&rsv_sug3=3&rsv_sug4=97&rsv_sug1=3&rsv_sug2=0&inputT=2568
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。
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。
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;
一定要全部??排序後再分?。否?就不能??了。

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