title: Join two tables with same rows in SQL
body: <p>Suppose I have two table like this:</p>
  
  <pre><code>table 1:               table 2:
  id      city           id      heading
  1201     X             1201     A
  1202     Y             1201     B
  1203     Z             1202     C
  1204     U             1202     D
                         1204     F
  </code></pre>
  
  <p>I want Output like this:</p>
  
  <pre><code>id  city id  heading
  1201 X   1201  A
  *null*   1201  B
  1202 Y   1202  C
  *null*   1202  D
  1203 Z   *null*
  1204 U   1204 F
  </code></pre>
  
  <p>Kindly Help me with this.</p>
  
  <p>Python is also acceptable if possible.</p>