$checkuser = mysql_query("SELECT username FROM users WHERE username='$username'");

 

$username_exist = mysql_num_rows($checkuser);

 

if($username_exist > 0){

    echo "I'm sorry but the username you specified has already been taken.  Please pick another one.";

    unset($username);

    include 'register.html';

    exit();

}

 

$tikrinam = mysql_query("SELECT vardas FROM lentele where vardas = '".$_POST['vardas']."' ");

$tikrinam2 = mysql_num_rows($tikrinam);

if($tikrinam2 != 0) {

echo"Toks vardas jau yra!";

}