how can i verify my login name if exists

[phani000]

hi
how can i check my login name in database from php page if it already exists
. so that i should not allow the same login name for another user . can any on help me with simple code

[zorgi]

If SQL command of similar structure as this one

"SELECT loogin_name FROM users_table WHERE loogin_name = '$entered_login_name' "

returns anything than the chosen name already exists. Table, table field and variable names should be those in your system. I just made them up for explaining purposes.

Hope this helps

[shabinesh]

$result = mysql_query("select name from table where name = new_login_name");
$row = mysql_fetch_array($result);
if($row[0]) 
      echo "Err: select different name";
else 
     echo "okay, no prob with login name";
 
 

I guess this could be a hint :)

[phani000]

thanx for your help but i am getting this error


Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in


line 8
okay, no prob with login nameMail Sent.Error: Column count doesn't match value count at row 1

[Atli]

That was not a copy/paste-able code. You need to re-write the SQL query and add error checking before it can work.

Post your code here and we may be able to point you in the right direction.

[phani000]

<?php
 include 'conifig.php';
 
 $pass=md5($_POST[password]);
$sql="INSERT INTO meconzee1_user VALUES ('','$_POST[firstname]','$_POST[lastname]','$_POST[middlename]','$_POST[radio]' ,'$_POST[loginname]','$pass',
'$_POST[dateofbirth]','$_POST[address1]','$_POST[address2]','$_POST[state]','$_POST[city]','$_POST[country]','$_POST[pincode]','$_POST[mailid]','$_POST[answer1]','$_POST[answer2]','$_POST[answer3]')";
 $result = mysql_query("select name from table where name = new_$_POST[loginname]");
 $row = mysql_fetch_array($result);
 if($row[0]) 
       echo "Err: select different name";
 else 
      echo "okay, no prob with login name";
 
$to = $_POST[mailid];
$subject = "Test mail";
$message = " Hello! This is a simple email message.
               your account has been created with the following login credentials 
               username ='$_POST[loginname]'
               password ='$pass'";
$from = "[e-mail]";
$headers = "From: $from";
mail($to,$subject,$message,$headers);
echo "Mail Sent.";
if (!mysql_query($sql,$con))
  {
  die('Error: ' . mysql_error());
  }
 
echo"1 record is added";
 
mysql_close($con);
  ?>

this is my code

[Atli]

Ok. There are a lot of problems in that code.

For example:

• The code shabinesh posted was NOT supposed to be just copied into the middle of your project, unaltered. It was an example, which you have to adapt to your own project. The way you use it will not work. (Not well, at least.)
• All text values in SQL queries need to be quoted. If they are not, the query will fail. (See your SELECT query)
• You should NEVER put raw user input into a SQL query. If you do, you open yourself up to an SQL Injection attack. - All data meant to be included in a MySQL query should be run through the mysql_real_escape_string function first. - This is PHP security 101; the #1 security threat a PHP application faces. It is the first thing a hacker will try to exploit when attacking your web, so you should ALWAYS keep this in mind.
• Strings should always be quoted. This includes array element names:
  

  $stuff = $_POST[stuff]; // INCORRECT
  $stuff = $_POST['stuff']; // CORRECT
   
  $string = "Stuff: $_POST[stuff]"; // This may work...
  $string = "Stuff: {$_POST['stuff']}"; // But this is better.
   

[Markus]

Furthermore, you should be checking that your $result variable is valid, i.e., your query ran successfully.

$result = mysql_query( ... );
if ($result === FALSE) {
    /** Query failed */
    print mysql_error();
    exit;
}
$row = mysql_fetch_array();
/** ... */
 

Sounds like you need to brush up on your PHP/MySQL skills.

[shabinesh]

yes! its mere a hint, not copy-paste code. :D