Doctrine ORM : Calculated related entity count in one shot - symfony

Question

I've a User entity and a Product entity.
class User{
/*
* #ORM\OneToMany(targetEntity="Product", mappedBy="User")
*/
private $Products;
}
class Product{
/**
* #ORM\ManyToOne(targetEntity="User", inversedBy="Products")
* #ORM\JoinColumn(name="user_id", referencedColumnName="id")
*/
private $User;
}
Now I'm trying to display a html table of users, but I want to show each user's product count too.
By using following code I'm able to obtain the users objects.
$qb = $this->_em->createQueryBuilder();
$qb->select('usr')
->from('User', 'usr');
$query = $qb->getQuery();
But I don't know how to get the products count in one shot. Any help?

Answer 1

First, you should really create a repository class for your entities if you want to create custom queries. Then you can simply run that query by injecting the entity repository as a service wherever you need it and then running the query method.
Second, you need to return a result from a doctrine query to retrieve anything from the database. If you want to determine the count of the objects returned, simply do this:
$qb = $this->_em->createQueryBuilder();
$qb->select('usr')
->from('User', 'usr');
$query = $qb->getQuery();
$count = count($query->getResult());
A doctrine query will return an array of objects matching your query. If you just want to return a count of the matching records, try something like this:
$qb = $this->_em->createQueryBuilder();
$qb->select('count(id)')
->from('User', 'usr');
$query = $qb->getQuery();
$count = $query->getSingleScalarResult();
Or to just get a count of Product objects for that user, from within the User repository class:
$qb = $this->_em->createQueryBuilder('usr');
$qb->select('count(p.id)')
->from('usr.Products', 'p');
return $qb->getQuery()->getSingleScalarResult();