title: How to convert separated Year(int), Month(int) and Day(int) columns into DateTime
body: <p>Our ERP system holds year, month and day in separate int columns. I want to combine those 3 int columns into one DateTime, How can I convert it in the SQL Server.</p>
  
  <pre><code>Year | Month | Day
  --------------------
  2016 | 1     | 23 
  </code></pre>