babaduk47 has created Issue #3474: Incorrect sorting in MongoDB when using chunkById in laravel-mongodb. This Jira ticket was filed by GromNaN

Issue Text:

• Laravel-mongodb Version: 12.47.0
• PHP Version: 8.4
• Database Driver & Version:

Description:

When using the `chunkById()` method with a model using the MongoDB driver, an incorrect sort query is generated with a duplicate `_id` key and a numeric key "0".

Steps to reproduce

```php
Item::query()
->orderBy('id')
->chunkById(100, fn() => throw new \Exception('test'));
```

Expected behaviour

The correct sort should look like this:
```json
{
"find": "items",
"filter": {
"$and": [
{ "_id":

{ "$ne": null }

},

{ "deleted_at": null }

]
},
"limit":

{ "$numberInt": "100" }

,
"sort": {
"_id":

{ "$numberInt": "1" }

}
}
```

Actual behaviour

```json
{
"find": "items",
"filter": {
"$and": [
{ "_id":

{ "$ne": null }

},

{ "deleted_at": null }

]
},
"limit":

{ "$numberInt": "100" }

,
"sort": {
"0":

{ "$numberInt": "1" }

,
"_id":

{ "$numberInt": "1" }

}
}
```

Issue: The sort section contains an incorrect key `"0"` along with _id.

Root Cause

The problem arises from differences in the `orders` storage structure between Illuminate and MongoDB:

Illuminate: `orders` is an array of objects with `column` and `direction` keys
MongoDB: `orders` is an object (associative array)

In the `removeExistingOrdersFor()` method of the `Builder` class:

```php
protected function removeExistingOrdersFor($column)
{
return (new Collection($this->orders))
->reject(fn ($order) => isset($order['column']) && $order['column'] === $column)
->values()
->all();
}
```

Problems:

• The `reject()` method doesn't filter orders correctly for MongoDB (since the data structure is different)
• Calling `values()` reindexes the array with numeric keys, causing the loss of original object keys in orders
• As a result, we get the key "0" instead of removing the existing sort