title: Linq union usage?
body: <p><strong>Sql:</strong></p>
  
  <pre><code>SELECT date,total_usage_T1 as TotalUsageValue,'T1' as UsageType FROM TblSayacOkumalari
  UNION ALL
  SELECT date,total_usage_T2 as TotalUsageValue,'T2' as UsageType FROM TblSayacOkumalari
  </code></pre>
  
  <p>And I try to do to convert it to linq</p>
  
  <pre><code>IEnumerable&lt;TblSayacOkumalari&gt; sayac_okumalari = entity.TblSayacOkumalari
  .Select(x =&gt; new 
      { x.date, x.total_usage_T1 })
  .Union(entity.TblSayacOkumalari.Select(x =&gt; new 
      { x.date, x.total_usage_T2 }));
  </code></pre>
  
  <p>But I dont know how to convert <code>'T1' as UsageType</code> to linq. Also my union using is incorrect too.</p>
  
  <p>My table fields like this:</p>
  
  <pre><code>| date | total_usage_T1 | total_usage_T2 |
  
  | 2010 |             30 |             40 |
  | 2011 |             40 |             45 |
  | 2012 |             35 |             50 |
  </code></pre>
  
  <p>I want like this</p>
  
  <pre><code>| date | TotalUsageValue | UsageType     |
  
  | 2010 |             30 |             T1 |
  | 2011 |             40 |             T1 |
  | 2012 |             35 |             T1 |
  | 2010 |             40 |             T2 |
  | 2011 |             45 |             T2 |
  | 2012 |             50 |             T2 |
  </code></pre>
  
  <p>I tried very hard, but could not. Please help.</p>