title: rownum / fetch first n rows
body: <pre><code>select * from Schem.Customer 
    where cust='20' and cust_id &gt;= '890127'
    and rownum between 1 and 2 order by cust, cust_id;
  </code></pre>
  
  <p>Execution time appr 2 min 10 sec</p>
  
  <pre><code>   select * from Schem.Customer where cust='20' 
     and cust_id &gt;= '890127' 
     order by cust, cust_id fetch first 2 rows only ;
  </code></pre>
  
  <p>Execution time appr 00.069 ms</p>
  
  <p>The execution time is a huge difference but results are the same. My team is not adopting to later one. Don't ask why.</p>
  
  <p>So what is the difference between Rownum and fetch first 2 rows and what should I do to improve or convince anyone to adopt.</p>
  
  <p>DBMS : DB2 LUW</p>