title: MySQL insert but update/ignore duplicate
body: <p>This is my table with some sample data</p>
  
  <pre><code>C ID | D ID    | Details |
  --------------------------
   a   | b_data1 | d1      |
   a   | b_data2 | d2      |
   b   | b_data1 | d1      |
   b   | b_data2 | d2      |
   c   | b_data1 | d1      |
   c   | b_data2 | d2      |
  </code></pre>
  
  <p>When I run this query##</p>
  
  <p><code>INSERT IGNORE INTO table_name (C_ID, D_ID, Details) VALUES ('C', 'b_data3','d3') ('C', 'b_data2','d2')</code></p>
  
  <p>It inserts both those rows when it's supposed to ignore the second value pair <code>('C', 'b_data2','d2')</code></p>
  
  <p>No indexes /primary key are defined.</p>
  
  <p>I want to make sure there is no duplicate row, means data in three columns combined should make the row unique. I can't make it unique .As I have illustrated here, a can keep same content as b but a should not have a duplicate.</p>