title: excel: how to delete the contents of cell A if it equals cell B
body: <p>Am running Excel 2013 under Windows 7.</p>
  
  <p>I have an Excel table that has 700,000+ rows. Columns A and B have identification codes.</p>
  
  <p>For each row I have three scenarios: 1) ID code is in cell A; 2) ID code is in cell B; 3) ID code is in cell A and cell B.</p>
  
  <p>For scenario #3, I want to delete the contents of cell A - in effect, removing the duplicate value in cell A.</p>
  
  <p>Once that is done, I'll combine Columns A and B into a single Column of identification codes (which I know how to do).</p>
  
  <p>Please help me code this statement:</p>
  
  <p>For each row where the value in cell A = the value in cell B, delete the value in cell A.</p>