title: Excel: Compare string between 2 columns, if match, trim/delete the matched string
body: <p>I am not good at advanced Excel formula and need help with data cleanup in excel for migration purpose. This is my scenario: </p>
  
  <pre><code>Column A                                             Column B 
  
  DocName                                              EmployeeName 
  ACCT6789_John_Smith_ACCOUNT_DOC_25_JAN_2007          John_Smith
  ACCT1122_Jane_Doe_ACCOUNT_DOC_EID00022_21_DEC_2009   Jane_Doe
  ACCT1462_Phil_Morris_ACCOUNT_DOC_EID0252             Phil_Moris
  </code></pre>
  
  <p>I need ColumnA's string to find exact match against ColumnB. If matched, then delete that matched string from ColumnA. If no exact match, there will be no action and the script will continue checking the next row. I know there will be issue with double underscore, and I hope to only have one underscore between any 2 words.</p>
  
  <p>The desired results for example above will be: </p>
  
  <pre><code>ACCT6789_ACCOUNT_DOC_25_JAN_2007              John_Smith 
  ACCT1122_ACCOUNT_DOC_EID00022_21_DEC_2009     Jane_Doe
  ACCT1462_Phil_Morris_ACCOUNT_DOC_EID0252      Phil_Moris
  </code></pre>