title: sql select statement with minus zero (-0) in calculation
body: <p>Came across this bit of legacy code today.  Wondering if there is some weird and wonderful meaning to its use.  I doubt it but thought it worth checking before I remove its usage.</p>
  
  <pre><code>select ...
      Amount = isnull(ARTL.Amount, 0) - 0,
      Retainage = isnull(ARTL.Retainage, 0) - 0,
      DiscOffered = ARTL.DiscOffered - 0,
  from tables ...
  </code></pre>
  
  <p>All three fields are numerics and the outcomes would be:<br></p>
  
  <pre><code>variable=null     0 - 0 = 0
  variable=0        0 - 0 = 0
  variable=-number  -number - 0 = -number
  variable=+number  +number - 0 = +number
  </code></pre>