php mysql 登录验证?

$conn= mysql_connect('localhost','root','密码') or die("无法连接数据库，请重试")

mysql_select_db('studentsystem') or die("无法选择数据库，请重试")

$set="select * from manager where username='".$_POST['username']."'

and password='".$_POST['pass']."'"

////重点在这里

$Result = mysql_query($set)// 结果集

$rows= mysql_fetch_array($Result,MYSQL_ASSOC) //读取数据

////重点在这里

if($rows){

echo "成功"

}else {

echo '不成功'

}

mysql_free_result($Result)

$conn = mysql_connect("localhost","root","")

mysql_select_db("homework", $conn)

mysql_query("SET NAMES 'UTF8'",$conn)

$username=$_POST['user_email']

$password=$_POST['password']

$sql = "select * from user where username='$username' and password='$password'"

$Result = mysql_query($sql, $conn)

$onerow = mysql_fetch_array($Result)

if (  $onerow )

    echo "正确"

else

    echo "错误"

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