所以我正在尝试为我的网站创建一个排名系统,但是由于许多记录都有相同的分数,它们都有相同的排名,有什么方法可以避免这种情况吗?
目前有
$conn = $db->query("SELECT COUNT( * ) +1 AS 'position' FROM tv WHERE points > ( SELECT points FROM tv WHERE id ={$data['id']} )");
$d = $db->fetch_array($conn);
echo $d['position'];
和DB结构
我正试图在Jelastic上运行ElasticSearch 5.0.1。在启动期间,它会打印到日志中:
max file descriptors [4096] for elasticsearch process is too low,
increase to at least [65536] max virtual memory areas vm.max_map_count
[65530] is too low, increase to at least [262144]
如何更改这些参数?增加预留云量并没有帮助。
我试图在Plesk主机上托管Umbraco,但获得了安全异常,我还试图将CAS信任级别更改为完全,但没有成功,请参阅下面的完整错误:
Security Exception
Description: The application attempted to perform an operation not allowed by the security policy. To grant this application the required permission please contact your system administrator or change the applicati
我已经构建了一个MVC3应用程序,并将其部署到第三方托管。在对连接字符串进行了一些认真的修改之后,我终于设法让它在主机上连接到SQL,并且应用程序运行良好,允许MVC的所有花哨都能工作(添加、更新、删除等)。
我离开网站运行了大约两个星期(使没有任何改变),现在当我浏览到它时,我得到了以下错误(当自定义错误关闭时)。
> Server Error in '/' Application.
>
> A network-related or instance-specific error occurred while
> establishing a con
我有一个项目表,以及它们来自哪个供应商: tabel items
Ttem ID - Item Title - Supplier - Date added
一个供应商可以提供多个物料,名称和供应商不是唯一的。
我想展示最新添加的56个项目,并从这56个项目中展示排名前十的供应商
所以我个人有:
select *
from items
order by dateadded desc
limit 56
对于供应商来说
select count(supplier) as howmany
from items
group by supplier
order by howmany desc