title: Difference between select count(*), count(0), count(100), count(Id) in SQL Server 2008?
body: <p>What is the difference between following SQL Server 2008 statements?</p>
  
  <pre><code>SELECT COUNT(*) FROM dbo.Regular_Report
  
  SELECT COUNT(0) FROM dbo.Regular_Report
  
  SELECT COUNT(1) FROM dbo.Regular_Report
  
  SELECT COUNT(100) FROM dbo.Regular_Report
  
  SELECT COUNT(ID) FROM dbo.Regular_Report
  </code></pre>