title: Update only time in a SQL Server DateTime column from another DateTime column in the same table
body: <p>I have a table that contains two <code>DateTime</code> columns. I would like to update my table so that it would copy the time only from column A and update that time only in column B without changing the actual date itself. Here is my data:</p>
  
  <pre><code>Column A                   | Column B
  ---------------------------+-------------------------
  2017-07-07 16:30:00.000    | 2017-08-30 22:05:00.000
  </code></pre>
  
  <p>The desired output is:</p>
  
  <pre><code>Column A                  | Column B
  --------------------------+------------------------
  2017-07-07 16:30:00.000   | 2017-08-30 16:30:00.000
  </code></pre>
  
  <p>I tried to get this done but I cannot figure out the correct syntax or if it is even possible. Thank you all in advance for your help and direction.</p>