title: Computed column should result to string
body: <p>Here is a snap of my database. </p>
  
  <p>Both col1 and col2 are declared as int.</p>
  
  <p>My ComputedColumn currently adds the Columns 1 and 2, as follows...</p>
  
  <pre><code>col1  col2  ComputedColumn
  1     2     3
  4     1     5
  </code></pre>
  
  <p>Instead of this, my ComputedColumn should join the columns 1 and 2 (includimg the <strong>'-'</strong> character in the middle) as follows...</p>
  
  <pre><code>col1  col2  ComputedColumn
  1     2     1-2
  4     1     4-1
  </code></pre>
  
  <p>So, what is the correct syntax?</p>