title: Concatenate first name, last name and middle name with comma
body: <p>I want to concatenate 3 columns in SQL server as below:</p>
  
  <pre><code>MAX(LTRIM(RTRIM((ISNULL(LastName,'') + 
      ', ' + 
      ISNULL(FirstName,'') + 
      ', ' + 
      ISNULL(MiddleName,''))))) AS FullName
  </code></pre>
  
  <p>I have used value of this column in SELECT clause as:</p>
  
  <pre><code>MAX(FullName) AS FullName,
  </code></pre>
  
  <p>I would like to handle NULL values, in case all 3 last name, middle name and first name are BLANK or NULL. The query used above will show " , , " in case all 3 columns are NULL or BLANK. But I want to show "N/A" in such case.</p>
  
  <p>Thanks in advance.</p>