title: Merge rows with same column value into 1 - Oracle
body: <p>I have an Oracle table looking like this:</p>
  
  <pre><code>+--+--+------+
  |DB|NR|Amount|
  +--+--+------+
  |BE|10|20    |
  +--+--+------+
  |BE|10|30    |
  +--+--+------+
  |FR|20|50    |
  +--+--+------+
  |FR|20|10    |
  +--+--+------+
  |DE|30|25    |
  +--+--+------+
  |BE|35|75    |
  +--+--+------+
  </code></pre>
  
  <p>Which query do I need to use to merge all the rows with the same DB and NR?</p>
  
  <p>This should be the result:</p>
  
  <pre><code>+--+--+------+
  |DB|NR|Amount|
  +--+--+------+
  |BE|10|50    |
  +--+--+------+
  |FR|20|60    |
  +--+--+------+
  |DE|30|25    |
  +--+--+------+
  |BE|35|75    |
  +--+--+------+
  </code></pre>
  
  <p>Thx in advance.</p>