title: Pick duplicate record within grouping records?
body: <p>I had an history table in which duplicate records are entered due to history_date_time column.
  Because of some process or loading issue i get this duplicate record.
  I used a query like </p>
  
  <pre><code>SELECT (col1, col2), COUNT(*)
  FROM table_name
  GROUP BY (col1, col2)
  HAVING COUNT(*) &gt;1;
  </code></pre>
  
  <p>I grouped a records based on <code>col1</code> and <code>col2</code> but the problem is
  i may have different column with different records. <code>I want to pick unique records within the grouping records by checking all columns</code></p>
  
  <p>How can i achieve this... using oracle sql query.. <code>i need query</code></p>
  
  <p>Sorry i dont have a proper table structure right now. </p>