Question

我正在运行的查询从PhpMyAdmin运行时返回2个结果，但从PHP脚本运行时不返回任何内容：

SELECT event_contacts.*, tasks.all_forms_in, tasks.drive_folder_empty FROM event_contacts, tasks WHERE event_contacts.eid = tasks.eid AND tasks.all_forms_in = 'y' AND tasks.drive_folder_empty = 'completed' AND event_contacts.email_sent_date IS NULL

我的PHP代码如下：

$query = mysql_query("SELECT event_contacts.*, tasks.all_forms_in, tasks.drive_folder_empty FROM event_contacts, tasks WHERE event_contacts.eid = tasks.eid AND tasks.all_forms_in = 'y' AND tasks.drive_folder_empty = 'completed' AND event_contacts.email_sent_date IS NULL");
    $result = mysql_query($query) or die($query."<br/><br/>".mysql_error());

    while ($row = mysql_fetch_array($query)){ 
         // do stuff
    }
}

为什么从PhpMyAdmin运行时返回2行，但从PHP脚本运行时“查询为空”死了？

Answer 1

您需要在while语句中使用$result而不是$query;

$query = mysql_query("SELECT event_contacts.*, tasks.all_forms_in, tasks.drive_folder_empty FROM event_contacts, tasks WHERE event_contacts.eid = tasks.eid AND tasks.all_forms_in = 'y' AND tasks.drive_folder_empty = 'completed' AND event_contacts.email_sent_date IS NULL");
    $result = mysql_query($query) or die($query."<br/><br/>".mysql_error());

    while ($row = mysql_fetch_array($result)){ 
         // do stuff
    }

Answer 2

在你的第一个

$query = mysql_query("SELECT event_contacts.*, tasks.all_forms_in, tasks.drive_folder_empty FROM event_contacts, tasks WHERE event_contacts.eid = tasks.eid AND tasks.all_forms_in = 'y' AND tasks.drive_folder_empty = 'completed' AND event_contacts.email_sent_date IS NULL");

必须只是一个字符串。像这样：

$query = "SELECT event_contacts.*, tasks.all_forms_in, tasks.drive_folder_empty FROM event_contacts, tasks WHERE event_contacts.eid = tasks.eid AND tasks.all_forms_in = 'y' AND tasks.drive_folder_empty = 'completed' AND event_contacts.email_sent_date IS NULL";

（没有mysql_query（）函数）。您正在下一个mysql_query（）调用中执行查询。

另外，正如@Umit Apari所说，必须使用mysql_query结果调用mysql_fetch_array（）。

但是，今天，你不应该使用mysql_ *函数，而是使用PDO函数。

从PHP运行时，MySQL查询返回空

2 个答案: