title: How can I use SUM() OVER()
body: <p>I can't understand this code's bug</p>
  
  <pre><code>ID      AccountID       Quantity
  1          1               10           Sum = 10
  2          1               5                = 10 + 5 = 15
  3          1               2                = 10 + 5 + 2 = 17
  4          2               7                = 7
  5          2               3                = 7 + 3 = 10  
  
  SELECT ID, AccountID, Quantity, 
         SUM(Quantity) OVER (PARTITION BY AccountID ) AS TopBorcT, 
  FROM tCariH
  </code></pre>