[Doctrine] [Symfony]在单个注释请求中进行多个联接（可能吗？）

Question

I'm working on a Symfony project (V3.4) and I'm using an existing DB (can't change it). To interact with it I use doctrine annotations and the work is well done! I manage to submit requests using JoinTable and JoinColumns but there is one last thing I don't know how to deal with ...

I have the following tables :

tables

I have the id from table A and I'm trying to get the libelle from the E table.

Is there a way to do it using annotations? For now I've already done it between 3 tables but I don't know how to do it for more :

@ORM\ManyToMany(targetEntity="")
 * @ORM\JoinTable(name="",joinColumns={@ORM\JoinColumn(
 name="",referencedColumnName="")}, inverseJoinColumns={@ORM\JoinColumn(
 name="",referencedColumnName="", unique=true)})

If it's not possible I'm open to suggestions.

Thanks!

Answer 1

By looking at your need and your schema, i can tell you that you don't need many to many relationship. You should bidirectional relation across the entities(tables).

I don't know which kind of relation you have right now, but assuming one-to-one, you can setup relations following way:

EntityA

/**
 * @OneToOne(targetEntity="EntityB", mappedBy="entityA")
 */
private $entityB;

EntityB

 /**
 * @OneToOne(targetEntity="EntityA", inversedBy="entityB")
 * @JoinColumn(name="entityA_id", referencedColumnName="id")
 */
private $entityA;
/**
 * @OneToOne(targetEntity="EntityC", mappedBy="entityB")
 */
private $entityC;

EntityC

/**
 * @OneToOne(targetEntity="EntityB", inversedBy="entityC")
 * @JoinColumn(name="entityB_id", referencedColumnName="id")
 */
private $entityB;
/**
 * @OneToOne(targetEntity="EntityD", mappedBy="entityC")
 */
private $entityD;

EntityD

 /**
 * @OneToOne(targetEntity="EntityC", inversedBy="entityD")
 * @JoinColumn(name="entityC_id", referencedColumnName="id")
 */
private $entityC;
/**
 * @OneToOne(targetEntity="EntityE", mappedBy="entityE")
 */
private $entityE;

EntityE

 /**
 * @OneToOne(targetEntity="EntityD", inversedBy="entityE")
 * @JoinColumn(name="entityD_id", referencedColumnName="id")
 */
private $entityD;

I didn't have time to test it. But it should be straight forward.

You can get libelle from E table following way:

$entityA = $entityRepositoryForA->find(a_id_here);
$entityA->getEntityB()->getEntityC()->getEntityD()->getEntityE->getLibelle();