Untitled

Username and Password validate doesn't work in PHP?
function queryByUserAndPass($tableName, $username, $password){
    $queryStatement = "SELECT * FROM ".$tableName." WHERE username='".$username."'
                      AND password='".$password."' LIMIT 1";
    return $queryStatement;
}

function checkLogIn() {

    if(isset($_POST['submit'])){
        $username = $_POST['username'];
        $password = $_POST['password'];
        $queryState = queryByUserAndPass("nepal_users", $username, $password);
        if( $resultQuery = mysql_query($queryState) ){
            $found_user= mysql_fetch_array($resultQuery);
            $_SESSION['id']=$found_user['id'];
            $_SESSION['username']=$found_user['username'];
            $message="succesful log in ".$_SESSION['username'];
            header("location:home.php");
            exit;
        }else {
            $message="error in log in";
        }

    }

}

if( $resultQuery = mysql_query($queryState) ){
        $found_user = mysql_fetch_array($resultQuery);
        if ($username === $found_user['username'] &&
          $password === $found_user['password']) {
            $_SESSION['id']=$found_user['id'];
            $_SESSION['username']=$found_user['username'];
            $message="succesful log in ".$_SESSION['username'];
            header("Location: home.php");
            exit;
        } else {
            echo "wrong username or password";
        }
    }else {
        $message="error from database: " . mysql_errno($resultQuery);
    }

$resultQuery = mysql_query($queryState);
if( $found_user = mysql_fetch_assoc($resultQuery)) {
    // do login stuff
    // note I used "fetch_assoc" above, because you don't use numeric indices here.
}
else $message = "Error";