title: How to write rownum in where clause in PostgreSQL
body: <p>I am quite new to Postgres database. I have one query:</p>
  
  <pre><code>select offer_id, offer_date
    from CMS_OFFER
   where ROWNUM &lt; 300
  </code></pre>
  
  <p>which executes in Oracle but in Postgres it is not excuted.
  I tried with row_number() also. It is not able to execute. Please help me: how I can achieve this?</p>