Get elements from LazyLoadCollection - doctrine-orm

Question

I have found Doctrine\Common\Collections\Criteria to be a very useful concept, if they worked for me.
In a symfony controller, I am calling this code:
$criteria = Criteria::create()
->where(Criteria::expr()->gt('position', 0))
->orderBy(['riskPosition', Criteria::ASC]);
$positions= $this->getDoctrine()->getRepository(DataCategory::class)->matching($criteria);
dump($positions->count()); // dumps 1, correct!
dump($positions);
foreach($positions as $r)
dump($r); // -> Unrecognized field: 0
dump($positions) gives
LazyCriteriaCollection {#881 ▼
#entityPersister: JoinedSubclassPersister {#849 ▶}
#criteria: Criteria {#848 ▼
-expression: Comparison {#836 ▶}
-orderings: array:2 [▶]
-firstResult: null
-maxResults: null
}
-count: 1
#collection: null
#initialized: false
}
As soon as I access an element of the returned array, I get an error
ORMException::unrecognizedField(0)
in vendor/doctrine/orm/lib/Doctrine/ORM/Persisters/Entity/BasicEntityPersister.php (line 1193)
But as soon as I want to access the elements (e.g. loop and dump) I get some error like An exception has been thrown during the rendering of a template ("Unrecognized field: 0").
As far as I have studied the code, the problem is that the query results have not been fetched from the database. Only count() works. How can I trigger this fetch?
Does it matter that my entity has #ORM\InheritanceType("JOINED")?
This code (circumventing the use of Criteria) does give correct results, but I'd like to use Criteria:
$riskPositions = $this->getDoctrine()->getRepository(DataCategory::class)
->createQueryBuilder('p')
->where('p.position > 0')
->orderBy('p.position', 'ASC')
->getQuery()
->execute();

Answer 1

The issue is caused by line:
->orderBy(['riskPosition', Criteria::ASC]);
Doctrine\Common\Collections\Criteria `s orderBy accepts an array argument where
Keys are field and values are the order, being either ASC or DESC.
github link
Apparently, there is a mistake at doctrine s documentation.
So doctrine thinks that "0", which is the 1st key of the array argument, is the field to sort by, but cannot find it.
To solve, change the above line to:
->orderBy(['riskPosition' => Criteria::ASC]);