title: GROUP BY doesn't return all rows per specific field
body: <p>Consider the DB : </p>
  
  <p>Account table </p>
  
  <p><img src="https://i.stack.imgur.com/0wKzt.gif" alt="enter image description here"></p>
  
  <p>With the records : </p>
  
  <p><img src="https://i.stack.imgur.com/7Raba.gif" alt="enter image description here"></p>
  
  <p>Clients table </p>
  
  <p><img src="https://i.stack.imgur.com/lUvtP.gif" alt="enter image description here"></p>
  
  <p>with the records : </p>
  
  <p><img src="https://i.stack.imgur.com/SdbBs.gif" alt="enter image description here"></p>
  
  <p>I want to get all the clients' names &amp; id , that are in Overdraft organized by client ID , so : </p>
  
  <pre><code>SELECT c.Client_id_number , a.Account_number ,  c.firstName_client , c.lastName_Client , a.Account_balance
  FROM Clients AS c 
  INNER JOIN Accounts AS a
  ON a.Client_id_number = c.Client_id_number
  WHERE a.Account_balance &lt; 0
  GROUP BY c.Client_id_number;
  </code></pre>
  
  <p>But this returned </p>
  
  <p><img src="https://i.stack.imgur.com/tODDn.gif" alt="enter image description here"></p>
  
  <p>Meaning the client <code>1234</code> with account <code>84</code> , and balance <code>-4000</code> doesn't appear ... where did I go wrong ? </p>