PHP: Opening url from database using header - php

Question

I am pretty new to php (mostly don't do web development at all actually) and, have gotten into it lately. I am trying to make a login page that redirects users after login to a unique URL linked to the user. So I wanted to have say 4 columns in the database: id, username, password, and redirect. And after a successful login to have the URL redirect to the redirect column in the db that is storing the user URL. The problem is the code that I have been working off of. To make a login I cant seem to have it redirect to the db column using the header("location:) line. Here is my code maybe you guys can kindly help me:
<?php
$host="sql1om"; // Host name
$username="b33_1033"; // Mysql username
$password="b33_1033"; // Mysql password
$db_name="test"; // Database name
$tbl_name="members"; // Table name
// Connect to server and select databse.
mysql_connect("$host", "$username", "$password")or die("cannot connect");
mysql_select_db("$db_name")or die("cannot select DB");
// username and password sent from form
$myusername=$_POST['myusername'];
$mypassword=$_POST['mypassword'];
// To protect MySQL injection (more detail about MySQL injection)
$myusername = stripslashes($myusername);
$mypassword = stripslashes($mypassword);
$myusername = mysql_real_escape_string($myusername);
$mypassword = mysql_real_escape_string($mypassword);
$sql="SELECT * FROM $tbl_name WHERE username='$myusername' and password='$mypassword'";
$result=mysql_query($sql);
// Mysql_num_row is counting table row
$count=mysql_num_rows($result);
// If result matched $myusername and $mypassword, table row must be 1 row
if($count==1){
// Register $myusername, $mypassword and redirect to file "login_success.php"
session_register("myusername");
session_register("mypassword");
header("location:login_success.php");
}
else {
echo "Wrong Username or Password";
}
?>
So I can't figure out how to add a db column variable to output the url from the redirect column in the
header("location:login_success.php);
Every time I try a variable in that line nothing happens
Any help would be appreciated. Please thoroughly explain I am a newbie at php. Thank-you!
Here is edited code that I got working (with help):
<?php
$host="localhost"; // Host name
$username="root"; // Mysql username
$password=""; // Mysql password
$db_name="test"; // Database name
$tbl_name="members"; // Table name
// Connect to server and select databse.
mysql_connect("$host", "$username", "$password")or die("cannot connect");
mysql_select_db("$db_name")or die("cannot select DB");
// username and password sent from form
$myusername=$_POST['myusername'];
$mypassword=$_POST['mypassword'];
// To protect MySQL injection (more detail about MySQL injection)
$myusername = stripslashes($myusername);
$mypassword = stripslashes($mypassword);
$myusername = mysql_real_escape_string($myusername);
$mypassword = mysql_real_escape_string($mypassword);
$sql="SELECT * FROM $tbl_name WHERE username='$myusername' and password='$mypassword'";
$result=mysql_query($sql);
// Mysql_num_row is counting table row
$count=mysql_num_rows($result);
// If result matched $myusername and $mypassword, table row must be 1 row
if($count==1){
// Register $myusername, $mypassword and redirect to file"login_success.php"
$_SESSION['username'] = $myusername;
$_SESSION['password'] = $mypassword;
$result = mysql_query("SELECT redirect FROM members");
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
header("Location: " . $row['redirect']);
}
exit();
}
else {
echo "Wrong Username or Password";
}
?>

Answer 1

You need to fetch your results into an associative array:
$row = mysql_fetch_assoc($result)
Then simply use header("Location: $row['redirect']");
Enclosing a string in double quotes enable you to insert a variable in there.
Alternatively, you can also concatentate: header("Location: " . $row['redirect']);
Your SQL results will be stored in an associatively array called $row. To access the redirect column, use $row['redirect']. Of course, $row will only be populated if a row or rows are found.
Finally, it is good practice to have an exit() to immediate stop script execution if you are redirecting.
Your code would look like:
$sql="SELECT * FROM $tbl_name WHERE username='$myusername' and password='$mypassword'";
$result=mysql_query($sql);
// Mysql_num_row is counting table row
$count=mysql_num_rows($result);
// If result matched $myusername and $mypassword, table row must be 1 row
if($count==1){
// Register $myusername, $mypassword and redirect to file "login_success.php"
$_SESSION['username'] = $myusername;
$_SESSION['password'] = $mypassword;
$row = mysql_fetch_assoc($result);
header("Location: $row['redirect']");
exit();
}else {
echo "Wrong Username or Password";
}