Grouping select with partial - postgresql

Question

Hello i have here this code:
public function getConversations($user, $limit, $page)
{
$offset = ($page - 1) * $limit;
$qb = $this->createQueryBuilder('message');
$qb
->select('message, partial o.{id}, partial userFrom.{id, username, avatar}, partial userTo.{id, username, avatar}, partial availability.{id, timeFrom}')
->leftJoin('message.from', 'userFrom')
->leftJoin('message.to', 'userTo')
->leftJoin('message.order', 'o')
->leftJoin('o.availabilities', 'availability')
->where($qb->expr()->orX(
$qb->expr()->eq('message.from', ':user'),
$qb->expr()->eq('message.to', ':user')
))
->setParameter('user', $user)
->setFirstResult($offset)
->setMaxResults($limit)
->addOrderBy('message.created', Criteria::DESC);
return $qb->getQuery()->getArrayResult();
}
I want to get only last message connected to each order. If i have 2 messages to order it gives me 2 rows but i need only one (the last one). I tried to use GROUP BY but it didn't work well. It wanted me to put all foreign ids to group by and then the result was really bad.
Result for this is:
{
"id": "813fa986-f89b-411d-8324-727e427cbc01",
"isRead": false,
"created": {
"date": "2016-12-12 18:01:00.000000",
"timezone_type": 3,
"timezone": "UTC"
},
"content": "Hello to you too",
"contentType": "text",
"from": {
"id": "3e1806d6-f47e-48b4-afdb-1081d9555a3f",
"avatar": "",
"username": "User two"
},
"to": {
"id": "52ead9fa-b498-400b-967d-b49886ab3118",
"avatar": "",
"username": "User one"
},
"order": {
"id": "8349e718-405a-4e88-8155-3896e9a89fdf",
"availabilities": [
{
"id": "9ddc07e0-be3d-453c-b12f-0ee31bfce444",
"timeFrom": {
"date": "2016-12-03 12:00:00.000000",
"timezone_type": 3,
"timezone": "UTC"
}
}
]
}
},
{
"id": "813fa986-f89b-411d-8324-727e427cbc00",
"isRead": false,
"created": {
"date": "2016-12-12 18:00:00.000000",
"timezone_type": 3,
"timezone": "UTC"
},
"content": "Helllooooooo",
"contentType": "text",
"from": {
"id": "52ead9fa-b498-400b-967d-b49886ab3118",
"avatar": "",
"username": "User one"
},
"to": {
"id": "3e1806d6-f47e-48b4-afdb-1081d9555a3f",
"avatar": "",
"username": "User two"
},
"order": {
"id": "8349e718-405a-4e88-8155-3896e9a89fdf",
"availabilities": [
{
"id": "9ddc07e0-be3d-453c-b12f-0ee31bfce444",
"timeFrom": {
"date": "2016-12-03 12:00:00.000000",
"timezone_type": 3,
"timezone": "UTC"
}
}
]
}
and should be just like this:
{
"id": "813fa986-f89b-411d-8324-727e427cbc01",
"isRead": false,
"created": {
"date": "2016-12-12 18:01:00.000000",
"timezone_type": 3,
"timezone": "UTC"
},
"content": "Hello to you too",
"contentType": "text",
"from": {
"id": "3e1806d6-f47e-48b4-afdb-1081d9555a3f",
"avatar": "",
"username": "User two"
},
"to": {
"id": "52ead9fa-b498-400b-967d-b49886ab3118",
"avatar": "",
"username": "User one"
},
"order": {
"id": "8349e718-405a-4e88-8155-3896e9a89fdf",
"availabilities": [
{
"id": "9ddc07e0-be3d-453c-b12f-0ee31bfce444",
"timeFrom": {
"date": "2016-12-03 12:00:00.000000",
"timezone_type": 3,
"timezone": "UTC"
}
}
]
}
}