PHP 5.2.6 & MySQL 5.0 Help

[XP On CD]

Hello, I'm Working On A Project With My Own Server I Built A Few Days Ago And This Is My Code:

----regstp1.html----
__________________
----START----
<title>TBCH Registration Step 1 - Query</title>
<center>
<form action="regstp2.php" method="post">
Username: <input type="text" name="user" maxlength="10" size="10" />
</br>
</br>
Password: <input type="password" name="pass" maxlength="10" size="10" />
</br>
</br>
<input type="submit" value="Submit" />
</form>
</center>
----END---

----regstp2.php----
__________________
----START----
<?php
$user = $_POST['user'];
$pass = $_POST['pass'];
$epass = hash("sha256", $pass);

mysql_connect("localhost", "root", "Not_Giving_It_Out") or die(mysql_error());
mysql_select_db("mysql") or die(mysql_error());

mysql_query("INSERT INTO members
(username, password) VALUES('$user', '$epass' ) ")
or die(mysql_error());
?>
----END---

I'm Wanting To Make It Check & Prevent Registration If That Current User Exists. Any Suggestions?

[Redcore]

Before you enter the new username, just make another query that checks if they exist.

PHP Code:

$check_query = mysql_query("SELECT username FROM members WHERE username = '$user'")
or die(mysql_error());
$num = mysql_numrows($check_query);

if($num!=0)
   {
    die("ERROR: This username already exists.");
   } 


Instead of just killing the process, you could always make it go to your custom error page (or go back to the registration page with the error code to display) via the HEADER function.

Also, take note that I initialized a variable for the query. You should always do this for your queries AND connection strings (so you can kill the connection when you're through with it - good practice).

Hope this helps :)

[XP On CD]

Thank You So Much It Helped Alot!!!