title: Left join doesn't return all results from first table
body: <p>I have a table that is used for reference (number), as follows</p>
  
  <pre><code>----------------------------
  Id | Name | Description    |
  ----------------------------
  1    One    The number one
  2    Two    The number two
  3    Three  The number three
  </code></pre>
  
  <p>And then another table (user_number) that references these values but for specific users</p>
  
  <pre><code>--------------------------
  Id | User_Id | Number_Id |
  --------------------------
  1    400      1
  2    400      2
  </code></pre>
  
  <p>I want to retrieve all the results of the first table but I want to see where they match up also. I have tried to use the following query but it only returns what an INNER JOIN would return</p>
  
  <pre><code>SELECT n.Id, n.Name, n.Description, un.Id As Active_Number
  FROM number n
  LEFT JOIN user_number un
  ON n.Id = un.Id
  WHERE un.User_Id = 400;
  </code></pre>
  
  <p>This query returns:</p>
  
  <pre><code>[
      {
          "Id": 1,
          "Name": "One",
          "Description": "The number one",
          "Active_Number": 1
      },
      {
          "Id": 2,
          "Name": "Two",
          "Description": "The number two",
          "Active_Number": 2
      }
  ]
  </code></pre>
  
  <p>However this doesn't return the third set of values from the number table.</p>