title: Create a Common Identifier Across Columns with the Same Data
body: <p>I have a dictionary containing the original word, and altforms of the word. What I have currently is something like this:</p>
  
  <pre><code>|---------------------|---------------------|------------------|
  |         WordID      |         Word        |     OrigWord     |
  |---------------------|---------------------|------------------|
  |         1           |          aah        |       null       |
  |---------------------|---------------------|------------------|
  |         2           |         aahs        |        aah       |
  |---------------------|---------------------|------------------|
  |         3           |         aahed       |        aah       |
  |---------------------|---------------------|------------------|
  |         4           |        aahing       |        aah       |
  |---------------------|---------------------|------------------|
  </code></pre>
  
  <p>I have around 270,000 words in the dictionary with a similar layout to this.</p>
  
  <p>Is there a fairly simple way to create an ID for each inflected form that links back to the original word similar to below?</p>
  
  <pre><code>|---------------------|---------------------|---------------------|------------------|
  |         WordID      |         LinkID      |         Word        |     OrigWord     |
  |---------------------|---------------------|---------------------|------------------|
  |         1           |         null        |          aah        |       null       |
  |---------------------|---------------------|---------------------|------------------|
  |         2           |         1           |         aahs        |        aah       |
  |---------------------|---------------------|---------------------|------------------|
  |         3           |         1           |         aahed       |        aah       |
  |---------------------|---------------------|---------------------|------------------|
  |         4           |         1           |        aahing       |        aah       |
  |---------------------|---------------------|---------------------|------------------|
  |         5           |         null        |      aardvark       |       null       |
  |---------------------|---------------------|---------------------|------------------|    
  |         6           |         5           |      aardvarks      |     aardvark     |
  |---------------------|---------------------|---------------------|------------------| 
  </code></pre>
  
  <p>EDIT:</p>
  
  <p>Added second example word to further explain LinkID functionality</p>