title: cbind different length of data frames based on column
body: <p>I have 2 dataframes:</p>
  
  <pre><code>df1
  name stock_1 stock_2
  A      11      12
  B       9       2
  C       1       3
  
  df2
  name stock_1
  D     2
  E     4
  </code></pre>
  
  <p>expected output:</p>
  
  <pre><code> name stock_1 stock_2
      A      11      12
      B       9       2
      C       1       3
      D     2        NA
      E     4        NA
  </code></pre>
  
  <p>the name and stock_1 names of columns. I try to cbind the 2 df but it is not working. Is there any efficient way?</p>