title: Revert a change made in a dataframe
body: <p>I have a data frame called x. Now, I wanted to create a new column using mutate. I know how mutate works. </p>
  
  <pre><code>x &lt;- x %&gt;%
    mutate(column3 = column1+column2)
  </code></pre>
  
  <p>Now I also needed to select just 3rd column. Unfortunately, I piped the select statement too.</p>
  
  <pre><code>x &lt;- x %&gt;%
    mutate(column3 = column1+column2) %&gt;%
    select(column3)
  </code></pre>
  
  <p>Resulting just 1 column in my data frame. I want to revert this change made. Is there any way to do that ? </p>