title: Adding a new column with month extracted from a separate already existing "date" (mdy) column
body: <p><a href="https://i.stack.imgur.com/510Ez.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/510Ez.png" alt="a partial clip of the data set"></a></p>
  
  <p>Trying to add a new column in my data table denoting the month (either as a numeric value or character) using an already available column of "SetDate", which is in the format mdy.</p>
  
  <p>I'm new to R and having trouble. Thank you</p>