title: Insert a row into the table if it does not exist using SQL
body: <p>I want to insert a row into the table if it does not exist.
  I want to check if the <code>col1 , col2</code> combination exists in the table.If not I have to insert the data.I have written a query like below , but it is not working.Can some one please help me.</p>
  
  <pre><code>INSERT INTO TABLE1 (COL1 , COL2 , COL3, COL4) 
  VALUES ( 1234 , 4567 , 'test_name_int' , 'test_disp_name' )
  WHERE NOT EXISTS ( SELECT * FROM TABLE1 WHERE COL1 = 1234 and COL2 = '4567');
  </code></pre>