Question

我有两个表（客户，管理员）用户通过电子邮件和密码登录，我需要检查客户或管理表中是否存在电子邮件和密码。电子邮件是unquie，所以不会有问题。这是单向工作，显然我会有比这更好的数据库设计，但我必须使用给定的。我有这个：

$email = $_POST['email']; 
$password = $_POST['password'];

$sql = "SELECT * FROM customer, admin WHERE cus_email = '$email'
 AND cus_password = '$password' OR admin_email = '$email' AND admin_password = '$password'";

对于Joins不是很好，所以我没有尝试过这个。

感谢您的帮助：）

Answer 1

你真的需要一个UNION而不是JOIN：

SELECT username
  FROM Customer
 WHERE cus_email = ? AND cus_password = ?
UNION
SELECT adminname AS username
  FROM admin
 WHERE admin_email = ? AND admin_password = ?

您应该使用占位符 - 问号 - 或保护自己免受SQL Injection攻击。有一些功能可以帮助您在PHP中实现这一点。

Answer 2

SELECT cus_id as id, 'false' as IsAdmin 
FROM customer
WHERE cus_email = '$email' 
    AND cus_password = '$password' 
UNION ALL    
SELECT admin_id as id, 'true' as IsAdmin
FROM admin
WHERE admin_email = '$email' 
    AND admin_password = '$password'";

来自两个表的SQL查询

2 个答案: