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POHow do I check for existing username
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  1. POHow do I check for existing username
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    copied!<p>I would like to see if a username is already created... I seached, and the mysql_num_row() or whatever it is, doesn't seem to work, i get a T_STRING Error if i use that... Heres my code, that says it should work, but it doesn't, why?:</p> <pre><code>/*simple checking of the data*/ if(isset($_POST['login']) &amp;&amp; isset($_POST['pass']) &amp;&amp; ($_POST['pass'] == $_POST['confirm'])) { /*Connection to database logindb using your login name and password*/ $db=mysql_connect('localhost','user','pass') or die(mysql_error()); mysql_select_db('db'); /*additional data checking and striping*/ $_POST['login']=mysql_real_escape_string(strip_tags(trim($_POST['login']))); $_POST['pass']=mysql_real_escape_string(strip_tags(trim($_POST['pass']))); mysql_query("INSERT INTO profiles SET username='{$_POST['login']}',password='{$_POST['pass']}'",$db); /*If the database has been updated*/ if(mysql_affected_rows() &gt; 0) { $_SESSION['login'] = $_POST['login']; $login='Welcome '.$_SESSION['login']; } else { $login= 'This login name already exists.'; } mysql_close($db); } </code></pre> <p>And i did as showdev suggested but get an error:</p> <p>New code:</p> <pre><code>/*additional data checking and striping*/ $_POST['login']=mysql_real_escape_string(strip_tags(trim($_POST['login']))); $_POST['pass']=mysql_real_escape_string(strip_tags(trim($_POST['pass']))); mysql_query("INSERT INTO profiles SET username='{$_POST['login']}',password='{$_POST['pass']}'",$db); /*If the database has been updated if(mysql_affected_rows() &gt; 0) { $_SESSION['login'] = $_POST['login']; $login='Welcome '.$_SESSION['login']; } else { $login= 'This login name already exists.'; }*/ $sql="SELECT COUNT(*) FROM `profiles` WHERE `username`='$username' AND `password`='$password' LIMIT 0,1;" $q=mysql_query($sql) or die(mysql_error()); $r=mysql_fetch_row($q); if ($r[0]==0) { // insert new user } else { // user already exists } mysql_close($db); } </code></pre> <p>Error:</p> <p>Parse error: syntax error, unexpected T_VARIABLE in /home/teachert/public_html/php/register.php on line 34</p> <p>UPDATE:</p> <p>New Code:</p> <pre><code>mysql_query("INSERT INTO profiles SET `username`='{$_POST['login']}',`password`='{$_POST['pass']}' ON DUPLICATE KEY UPDATE `username`='{$_POST['login']}'",$db); /*If the database has been updated*/ if(mysql_affected_rows() == 1) { $_SESSION['login'] = $_POST['login']; $login='Welcome '.$_SESSION['login']; } else { $login= 'This login name already exists.'; } mysql_close($db); } </code></pre> <p>Still doesn't work</p>
 

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