拥有方的一对多单向查找原则

Question

Problem definition

So given this part of Doctrine documentation (and many other articles about bidirectional association and persistence problems), I have a one-to-many association that is unidirectional. It is between a Club and it's Staff members. From domain logic, the Club should own the Staff . For example, if I used document storage, Staff would be a member of Club . In 99.9% of domain cases, I have a club and want a list of its staffers.

However, I am having trouble implementing this idea in Doctrine. Because in Doctrine the ONE-TO-MANY relationship has only an inverse side. So even conceptually the following Entity definition is wrong, but I do not know any better.

Entity code

<?php

class Club
{
    /**
     * @ORM\Id
     * @ORM\Column(type="uuid", unique=true)
     * @ORM\GeneratedValue(strategy="CUSTOM")
     * @ORM\CustomIdGenerator(class="Ramsey\Uuid\Doctrine\UuidGenerator")
     */
    public ?UuidInterface $id;

    /**
     * @ORM\Column(type="string", name="name")
     */
    public string $name;

    /**
     * @ORM\OneToMany(targetEntity="Staff", mappedBy="club")
     */
    public Collection $staff;

    public function __construct(string $name)
    {
        $this->id       = Uuid::uuid4();
        $this->name     = $name;
        $this->staff    = new ArrayCollection();
    }

    public function addStaff(Staff $staff): void
    {
        $this->staff->add($staff);
    }

}

class Staff
{
    public const ROLE_OWNER = 'owner';

    /**
     * @ORM\Id
     * @ORM\Column(type="uuid", unique=true)
     * @ORM\GeneratedValue(strategy="CUSTOM")
     * @ORM\CustomIdGenerator(class="Ramsey\Uuid\Doctrine\UuidGenerator")
     */
    public ?UuidInterface $id;

    /**
     * @ORM\Column(type="string", name="user_id")
     */
    public string $userId;

    /**
     * @ORM\Column(type="string", name="role")
     */
    public string $role;

    public function __construct(string $userId, string $role)
    {
        $this->id     = Uuid::uuid4();
        $this->userId = $userId;
        $this->role   = $role;
    }
}

But here comes the real problem. I have ONE use case, where I want to find clubs for the appropriate staffer. It is a (ONE-)MANY-ONE problem, with the caveat that the first one is not another Doctrine entity, but a userId for the Staff entity.

So I tried several approaches to getting Club entities given userId :

Failed attempts

<?php
   // 1. Naive solution, just try to use the `ObjectRepository`
   // Will cause: You cannot search for the association field 'Club#staff', because it is the inverse side of an association. Find methods only work on owning side associations.
$staffers = $this->em->getRepository(Staff::class)->findBy(['userId' => $ownerId]);
$clubs = $this->em->getRepository(Club::class)->findBy(['staff' => $staffers]);

   // 2. Use `QueryBuilder` naively
   // Will cause: [Semantical Error] line 0, col 131 near 'staff = s.id': Error: Invalid PathExpression. StateFieldPathExpression or SingleValuedAssociationField expected
         $qb = $this->em->createQueryBuilder();
         $query = $qb->select('c')
         ->from(Club::class, 'c')
         ->join(Staff::class, 's', Join::WITH, 'c.staff = s.id')
         ->where('s.userId = :id')
         ->setParameter('id', $ownerId)
         ->getQuery();

    // 3. Use `QueryBuilder` with knowledge if actual DB columns
    // Will cause: [Semantical Error] line 0, col 138 near 'club_id WHERE': Error: Class Staff has no field or association named club_id
         $qb = $this->em->createQueryBuilder();
         $query = $qb->select('c')
         ->from(Club::class, 'c')
         ->join(Staff::class, 's', Join::WITH, 'c.id = s.club_id')
         ->where('s.userId = :id')
         ->setParameter('id', $ownerId)
         ->getQuery();

    // 4. Create query directly
    // Will cause: [Semantical Error] line 0, col 125 near 'staff = s.id': Error: Invalid PathExpression. StateFieldPathExpression or SingleValuedAssociationField expected
                $query = $this->em->createQuery('SELECT c FROM ' . Club::class . ' c JOIN ' . Staff::class . ' s WITH c.staff = s.id WHERE s.userId = :id')->setParameter('id', $ownerId);

WHat am I looking for?

• a unidirectional association between Club and Staff , so that I don't have to be careful about persistence, performance, inconsistencies, etc. Just all the problems of bidirectional associations.
• either:
  • a possible rework of the entities/associations
  • a way to retrieve Club entities, given staff.userId

Answer 1

A solution that is working, but I am unable to provide an explanation as to why this one works and others do not.

<?php
$this->em->createQueryBuilder()
            ->select('c')
            ->from(Club::class, 'c')
            ->innerJoin(Staff::class, 's')
            ->where('s.userId = :owner')
            ->setParameter('owner', $ownerId)
            ->getQuery()
            ->getResult();