title: Efficient way of processing huge Datatable in C#.net
body: <p>I have a huge dataTable (around 500k-600k rows). I wanted to compute rows based on some specific columns.
  Ex: I have 3 columns name ID, type and value. I wanted to compute 'value' column based on 'Type'. I have done it using DataRow Filter - first get the unique 'ID', then for each 'type' compute value. This logic gets really complex and take longer to process. I'm not very good in LINQ, so i was wondering if i can do it better using LINQ or any other way?</p>
  
  <p>DataTable:</p>
  
  <pre><code>ID       type      value  
  --------------------------------
  2         100         5
  
  2         100         6
  
  2         200         10
  
  3         200         8
  
  3         200         9
  
  4         100         10
  
  4         200         15
  </code></pre>
  
  <p>The output i'm looking for is:</p>
  
  <pre><code>ID     Type          Value
  
  2       100            11
  
  2       200            10
  
  3       200            17
  
  4       100            10
  
  4       200            15
  </code></pre>