title: Modify Date without DateAdd or DateDiff
body: <p>Is it possible to modify the day part of a date without having to use DateAdd or having to calculate the date difference?</p>
  
  <pre><code>SET @ReturnDate = '5/16/2012'
  
  SET @ModifyDay = 20
  </code></pre>
  
  <p>Modify only <code>16</code> to <code>20</code></p>
  
  <p>Result should be <code>5/20/2012</code></p>
  
  <p>The reason for this is that I am translating vb code into a stored proc:</p>
  
  <pre><code>    Dim InvDate_Day_of_Month As Integer = CInt(Day(InvDate))
      PaymentDate = DateAdd(DateInterval.Month, 1, InvDate)
      PaymentDate = New Date(PaymentDate.Year, PaymentDate.Month, DayofTheMonth)
  </code></pre>