title: Find if value in column A contains value from column B?
body: <p>I have two columns- column E which extends upto 99504(values) and column I which extends to 2691(values).Both the columns contains filenames with extension.</p>
  
  <p>Something like this</p>
  
  <pre><code>E               I
  TSL_groups.mrk  pcbx_report.mrk
  abcd.mrk        jhuo.mrk
  </code></pre>
  
  <p>and so on...</p>
  
  <p>I want to find if the files in column I (heading Filename_B) exists in column E(heading Filename_A). If true, say TRUE in a new column let's say column K.</p>
  
  <p>How do I do that? TIA.</p>