Home Database Mysql Tutorial MySQL中按照多字段排序及问题解决_MySQL

MySQL中按照多字段排序及问题解决_MySQL

Jun 01, 2016 pm 01:04 PM
mysql Sort by multiple fields

因为在做一个项目需要筛选掉一部分产品列表中的产品,使其在列表显示时排在最后,但是所有产品都要按照更新时间排序。

研究了一下系统的数据库结构后,决定将要排除到后面的产品加为粗体,这样在数据库中的“ifbold”就会被标记为1,而其他产品就默认标记为0,然后就打算使用MySQL在Order By时进行多字段排序。

Order by的多条件分割一般使用英文逗号分割,所以我测试的SQL如下:

代码如下:


select * from {P}_product_con where $scl order by 'ifbold' asc,$myord desc limit $pagelimit"

但是运行后没有将”ifbold“正序,但是单纯正序”ifbold“却正常,调试了N久,无意中在phpMyAdmin中运行却发现正常,仔细比对后发现问题原来是来自于”ifblod“的引号上。改为下列语句就正常了:

代码如下:


select * from {P}_product_con where $scl order by `ifbold` asc,$myord desc limit $pagelimit

所以以后大家再程序中写SQL语句时也要注意引号的问题哦!

以上所述就是本文的全部内容了,希望大家能够喜欢。

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