Laravel Eloquent groupBy orderBy gives different results in MariaDB - laravel

Question

I have read about this already in SO and MariaDB knowledgeable about this incompatibility between Mysql and Mariadb. But I am not sure how to resolve this issue in Laravel Eloquent / DB queries.
My Problem: The groupBy orderBy query gives different results in MariaDB and MySql. It works fine in mySql by the results are in different order in MariaDB.
This is my query:
$messages = ChatMessages::select(DB::raw('t.*'))
->from(DB::raw('(SELECT * FROM chat_messages ORDER BY created_at DESC) t'))
->whereIn('message_id', $messageIds)
->groupBy('message_id')
->orderBy('created_at', 'DESC')
->paginate(3);
For example, lets say this is the chat_messages table:
+----+----------+---------------------+-----------+
| id | message_id | created_at | name |
+----+----------+---------------------+-----------+
| 1 | 1000 | 2017-01-01 06:03:40 | Anna |
+----+----------+---------------------+-----------+
| 2 | 1007 | 2017-01-02 07:13:20 | Becky |
+----+----------+---------------------+-----------+
| 3 | 1000 | 2017-01-03 08:20:12 | Christina |
+----+----------+---------------------+-----------+
| 4 | 1004 | 2017-01-03 08:20:15 | Dorothy |
+----+----------+---------------------+-----------+
| 5 | 1004 | 2017-01-04 09:25:45 | Emma |
+----+----------+---------------------+-----------+
| 6 | 1000 | 2017-01-05 10:30:10 | Fiona |
+----+----------+---------------------+-----------+
| 7 | 1007 | 2017-01-05 10:33:23 | Gigi |
+----+----------+---------------------+-----------+
| 8 | 1007 | 2017-01-06 12:46:34 | Heidi |
+----+----------+---------------------+-----------+
| 9 | 1000 | 2017-01-06 12:46:34 | Irene |
+----+----------+---------------------+-----------+
| 10 | 1007 | 2017-01-07 14:58:37 | Jane |
+----+----------+---------------------+-----------+
| 11 | 1007 | 2017-01-07 14:58:37 | Katy |
+----+----------+---------------------+-----------+
The query works fine in MySql database and the results are returned as this:
+----+----------+---------------------+-----------+
| id | message_id | created_at | name |
+----+----------+---------------------+-----------+
| 11 | 1007 | 2017-01-07 14:58:37 | Katy |
+----+----------+---------------------+-----------+
| 9 | 1000 | 2017-01-06 12:46:34 | Irene |
+----+----------+---------------------+-----------+
| 5 | 1004 | 2017-01-04 09:25:45 | Emma |
+----+----------+---------------------+-----------+
However, in MariaDB database, the results are returned incorrectly like this. It seems to group the message_id in ascending order first and then adding the orderBy to that:
+----+----------+---------------------+-----------+
| id | message_id | created_at | name |
+----+----------+---------------------+-----------+
| 4 | 1004 | 2017-01-03 08:20:15 | Dorothy |
+----+----------+---------------------+-----------+
| 2 | 1007 | 2017-01-02 07:13:20 | Becky |
+----+----------+---------------------+-----------+
| 1 | 1000 | 2017-01-01 06:03:40 | Anna |
+----+----------+---------------------+-----------+
I tried changing the query thought of using unique() instead like this:
ChatMessages::whereIn('message_id', $messageIds)
->orderBy('created_at', 'DESC')
->paginate(3)
->unique('message_id');
Although it works in MariaDB and MySql the same way, but the pagination is applied before the unique check and therefore returned lesser results:
+----+----------+---------------------+-----------+
| id | message_id | created_at | name |
+----+----------+---------------------+-----------+
| 11 | 1007 | 2017-01-07 14:58:37 | Katy |
+----+----------+---------------------+-----------+
| 9 | 1000 | 2017-01-06 12:46:34 | Irene |
+----+----------+---------------------+-----------+
How can I resolve this?

Answer 1

You are probabbly trying to do a "groupwise max". This can no longer be done by the trick of having a subquery with an ORDER BY.
A subquery, but definition, has no order. However, in the past, both MariaDB and MySQL would perform the ORDER BY, and that happened to be beneficial to the outer query.
MariaDB was first to ignore the inner ORDER BY; MySQL picked up on it later. Follow the tag [greatest-n-per-group] for various workarounds.