title: Symfony - Doctrine relationship - Returns relational model with null values
body: <p>First things first. I am totally new on Symfony, and I am trying to solve an issue but I don't know how. So, if my questions seem to weird to you, then please help me by explaining where I am wrong and thank you in advance.</p>
  
  <p>So, in my DB I have the following tables:</p>
  
  <p><code>payments</code>, with columns: <code>id</code>, <code>merchant_sevice_id</code>, <code>customer_id</code>, <code>status</code>, <code>type</code>, <code>created_at</code>, <code>amount_amount</code>, <code>amount_currency</code>. <code>payment_method_payment_method_type</code>, <code>payment_method_payment_method_id</code>, <code>vat</code> and <code>failed_reason</code>.</p>
  
  <p>and</p>
  
  <p><code>merchant_services</code> with columns: <code>id</code>, <code>payment_institution_id</code>, <code>account_id</code>, <code>name</code>, <code>capacity</code>, <code>capabilities</code>, <code>created_at</code>, <code>mid</code>, <code>status</code>, and <code>blocked_bins_id</code>.</p>
  
  <p>The two tables are connected with a <code>manyToOne</code> relationship. So, many payments could belong to one <code>Merchant</code></p>
  
  <p>Now, the problem is when I try to get one <code>Payment</code> and check the relationship with <code>Merchants</code>. The fields of the <code>Merchant</code> are all <code>nulled</code>, while in DB I have values.</p>
  
  <p>So a given record in <code>payments</code> table looks like that:</p>
  
  <pre><code>| id                                   | merchant_service_id                  | customer_id                          | status | type | created_at           | amount_amount | amount_currency | payment_method_payment_method_type | payment_method_payment_method_id     | vat | failed_reason |
  -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  | 0fede82a-b898-4287-83e3-8f7d28d576db | 548d36d9-f1e6-4854-b513-1559b2499b45 | 237369c4-feed-4e24-964a-638938c7940c | failed | SALE |  2018-06-15 07:36:28 | 100           | GBP             | card                               | f35f78c4-2da7-432a-ace5-c0829db448af | 5   |               |
  </code></pre>
  
  <p>And the related record in merchants is like that:</p>
  
  <pre><code>| id                                   | payment_institution_id               | account_id                           | name | capacity | capabilities | created_at          | mid | status | blocked_bins_id                      |
  -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  | 548d36d9-f1e6-4854-b513-1559b2499b45 | c7a02b53-6c8b-4aa9-b1af-1c5b4978d844 | 4d239c0f-1fa0-4d70-88b4-95b6f05e7bf5 | Test | 0        | ["AUTH"]     | 2018-06-06 06:36:15 | 53  | active | e3d6a222-68cd-468c-a78a-b0da8ff0caf9 |
  </code></pre>
  
  <p>Then, the output of my query in the DB seems like that:</p>
  
  <p><a href="https://i.stack.imgur.com/zOiIw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/zOiIw.png" alt="enter image description here"></a></p>
  
  <p>As you could see, the values of the <code>merchantService</code> are all null <em>(except the ID)</em>.</p>
  
  <p>So the question is, what it could make this problem? Could be a serializer? Is that a kind of Symfony issue? Actually I am looking for a hint on where to look for solution of that issue.</p>
  
  <p>Again sorry if my question is too weired, but I am really blocked and I don't know how to continue.</p>