where子句中的未知列

Question

此脚本应该检索已输入表单的Customer_First_Name和Customer_Last_Name的CustomerID。

$query  = "SELECT CustomerID FROM customer WHERE Customer_First_Name = `.$db_customer_first_name.` AND Customer_Last_Name = `.$db_customer_last_name.`";
$result = mysql_query($query)
or die(mysql_error());
echo $result;
echo $query;

当脚本运行时，我收到此错误：

  

未知专栏'。克里斯托弗。'在'where子句'

查询永远不会在屏幕上打印出来。

感谢任何帮助。

Answer 1

你的报价不好用'而不是勾选`

Answer 2

使用'代替`

$query  = "SELECT CustomerID FROM customer WHERE Customer_First_Name = '".$db_customer_first_name."' AND Customer_Last_Name = '".$db_customer_last_name."'";

Answer 3

您必须对字符串使用单引号。再试一次：

$query  = "SELECT CustomerID FROM customer WHERE Customer_First_Name = '".$db_customer_first_name."' AND Customer_Last_Name = '".$db_customer_last_name."'";

Answer 4

这应该有效：

$query  = "SELECT CustomerID FROM customer WHERE Customer_First_Name = '$db_customer_first_name' AND Customer_Last_Name = '$db_customer_last_name'";

您需要使用正常的单引号作为值。如果您使用双引号，也不需要断开字符串 - 在字符串中检测到变量。

确保你也正确地为mysql转义字符串以防止注入。

更好的是，看看转向mysqli并使用准备好的陈述。