我正在登录，我得到一个错误，从MySQL查询的行数计数。错误如下。
Warning: mysql_num_rows() expects parameter 1 to be resource, boolean given in /home/nzcraftn/public_html/bs/login.php on line 13
Warning: Cannot modify header information - headers already sent by (output started at /home/nzcraftn/public_html/bs/login.php:13) in /home/nzcraftn/public_html/bs/login.php on line 21
我正在使用这个代码登录。
<?php
session_start();
include('config.php');
$user = protect($_POST['username']);
$pass = protect($_POST['password']);
$salt = "a123b123";
$thepass = md5($salt.md5($pass));
$res = mysql_query("SELECT `username`,`password` WHERE (`username` = '$user' AND `password` = '$thepass')");
$count = mysql_num_rows($res);
if($count == 1) {
$_SESSION['user'] = $user;
print($_SESSION['user']);
//header('Location: /panel/index.php');
} else {
$_SESSION['errormsg'] = "<div style='color: #FF0000'>Invalid Login!</div>";
header('Location: index.php');
}
?>
您的语句中有错误，因此mysql_query返回false。请在你的代码中添加错误检查(和调试日志)。
(您的SELECT缺少FROM条款)
通过自己在MySQL提示符中运行SQL查询来确保SQL查询正常工作。为SQL查询添加一些故障排除代码，如下所示:
$query = 'SELECT ...';
$res = mysql_query($query) or die(mysql_error()."'n".$query);