Doctrine2 custom records order - doctrine-orm

Question

I have simple query to get all pictures from database:
$this->createQueryBuilder('p')
->getQuery()
->getResult();
And I have array of ID's, which represents how they should be arranged in result array. How can I tell doctrine, to return these pictures in that specific order? For example, my "order array" is [3, 5, 9, 1, 10] and I want to get results in that particular order.

Answer 1

There are several ways to do this. If you're using postgresql you can try one of the raw queries here: ORDER BY the IN value list . If you're using mysql you can try the suggestions here: Ordering by the order of values in a SQL IN() clause
If you instead want to do it through straight Doctrine you could create a generic mapper function that orders the results. For very large result sets you may hit performance issues since you have O(n^2). But it's a little simpler than trying to make your own custom Doctrine function to handle it, relying on database implementation.
Say your query returns 5 results with the following ids: (95, 4, 1, 33, 35). Now say you want them returned as (1, 35, 4, 33, 95):
$entities = $em->getRepository('YourBundle:Picture')->findBy(/*some criteria*/);
$orderFunction = function($id) use ($entities)
{
foreach ($entities as $entity)
{
if ($entity->getId() == $id) {
return $entity;
}
}
};
$orderAs = array(1, 35, 4, 33, 95);
$orderedEntities = array_map($orderFunction, $orderAs);
Now your $orderedEntities array will be in the order you specified.