title: Returning rows based on the count(value) = 1
body: <p>I have a query similar to this:</p>
  
  <pre><code>select
      clm.CLM_ID,
      csv.CSV_PRC_CD
  FROM
      CLM_CLAIM clm inner join CSV_CLM_SRV csv on clm.CLM_iD = csv.CSV_CLM_ID
  GROUP BY
      clm.CLM_ID,
      csv.CSV_PRC_CD
  </code></pre>
  
  <p>My results look something like this:</p>
  
  <pre><code>CLM_ID      CSV_PRC_CD     
  ----------- ---------------
         5087 0270           
         5087 0305           
         5087 0351           
         5087 0637           
         5087 0730           
       365294 99221          
       406116 0250           
       406116 0300           
       406116 0450           
       523504 99202          
       602677 73080          
       602677 73100          
       901343 97002          
       901343 97014          
      1040368 00190          
      1250851 93306   
  </code></pre>
  
  <p>What I'm trying to accomplish is to return only the rows that have only ONE CSV_PRC_CD associated with a CLM_ID. So my results should look like:</p>
  
  <p>CLM_ID      CSV_PRC_CD     </p>
  
  <hr>
  
  <pre><code> 365294 99221          
   523504 99202          
  1040368 00190          
  1250851 93306   
  </code></pre>
  
  <p>Anything where the <code>CLM_ID</code> has more than 1 <code>CSV_PRC_CD</code> associated with it should be omitted from my results.</p>