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在Joomla mysql查询中,表名的开头是什么意思?_Mysql_Joomla_Query Builder - Fatal编程技术网

在Joomla mysql查询中,表名的开头是什么意思?

在Joomla mysql查询中,表名的开头是什么意思?,mysql,joomla,query-builder,Mysql,Joomla,Query Builder,我有一个mysql查询,看起来像$query=SELECT*FROM\uu内容 表名开头的“\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu 如果没有定义,人们将不得不手动将前缀输入到每个需要访问数据库的扩展中,你可以想象这会很烦人 例如,如果数据库表前缀为j25,则: __content=j25\u content正如其他人所

我有一个mysql查询,看起来像$query=SELECT*FROM\uu内容

表名开头的“\uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu

如果没有定义,人们将不得不手动将前缀输入到每个需要访问数据库的扩展中,你可以想象这会很烦人

例如,如果数据库表前缀为j25,则:


__content=j25\u content

正如其他人所说,hash下划线序列'\u'是Joomla用于表名的前缀JDatabase类。注意:只有一个下划线,为了表名的可读性,将保留第二个下划线

当你第一次安装Joomla时!您可以选择设置前缀或使用当时随机生成的前缀。你可以读到

当您使用JDatabase类访问数据库时,它为您提供了一种抽象机制,这样您就可以与Joomla正在使用的数据库进行交互,而无需专门为MySQL、MSSQL或PostgreSQL等编写代码

当JDatabase在执行查询之前准备好查询时,它会用前缀setup When Joomla!已安装。e、 g

    // Get the global DB object.        
    $db = JFactory::getDBO();
    // Create a new query object.       
    $query = $db->getQuery(true);
    // Select some fields
    $query->select('*');

    // Set the from From segment
    $query->from('#__myComponents_Table');
稍后,当您执行查询时,JDatabase将把SQL的from段改为from

从myComponents表到


从jp25_myComponents_表中-如果前缀是jp25,则在执行它之前。

但是如果我使用mysql命令提示符运行该查询,它会说我正在生成sql错误语法谢谢,那么我的第二个问题呢?显示查询,您不尝试运行哪个请添加用于从数据库中提取数据的完整代码$query=SELECT*FROM\u内容不够by@US-武士和