pdo - JSON response not as expected using php -

i know simple question, can't find answer issue, maybe because basic php programming question. function using pdo (php):

<?php function getallusers(){     try {         $conn = getconnection(); //connects database, no explanation needed... uses pdo         $dbh = $conn->prepare("select * user;");         $dbh->execute();          $users = $dbh->fetchall(); //<---this maybe error          $conn = null;         return $users;     }catch (pdoexception $ex){         echo "error: ".$ex->getmessage();     } } ?> 

and when consume api i'm implementing, use other php script (using slim framework, still pretty understandable)

<?php $app->get("/user",function() use($app){      $app->response->headers->set("content-type","application/json");     $app->response->status(200);     $result = getallusers(); //call function getallusers     $app->response->body(json_encode($result)); }); ?> 

it works fine, results these:

[{"iduser":"1","0":"1","username":"asdasd","1":"asdasd","userpass":"password","2":"password"},{"iduser":"2","0":"2","username":"2312","1":"2312","userpass":"password","2":"password"}] 

and think repeated values "0":"1" , "1":"asdasd" , "2":"password"should not there, can't figure out how data want , not repeated values. appreciated

i'm not using pdo, "common" mysql queries , there same...you doubled values. 1 array associative , other indexed (0,1,2). , there option pass ("mysql_assoc" if recall well) associative array, without indexed one. there must similar option pdo.

$dbh->fetchall(pdo::fetch_assoc);

http://php.net/manual/en/pdostatement.fetchall.php