title: Subtract minute from DateTime in SQL Server 2005
body: <p>Suppose I have a datetime field whose value is <strong>2000-01-01 08:30:00</strong> 
  and a duration field whose value is say <strong>00:15</strong> (meaning 15 minutes) </p>
  
  <p>If I subtract these two, I should get <strong>2000-01-01 08:15:00</strong></p>
  
  <p>Also if I want to subtract <strong>1:15</strong> (means 1 hour 15 minutes), the output should be <strong>2000-01-01 07:15:00</strong></p>
  
  <p>I am trying <code>SELECT DATEDIFF(minute, '00:15','2000-01-01 08:30:00');</code> </p>
  
  <p>But the output is 52595055. How can i get the desired result?</p>
  
  <p>N.B.~ If I do <code>SELECT dateadd(minute, -15,'2000-01-01 08:30:00');</code> , I will get the desired result but that involves parsing the minute field. </p>
  
  <p>Edit:</p>
  
  <p>As per the answers, every one is suggesting converting everything into minutes and then to subtract - so if it is 1:30, i need to subtract 90 minutes. That's fine. Any other way without converting to minutes?</p>