title: HOW to structure SQL CASE STATEMENT with multiple conditions
body: <p>I would like to convert the below logic into a SQL query, and i know that it can be acheived using a CASE WHEN THEN ELSE statement , but i am not sure how i can put it together in the query. Please help.</p>
  
  <ol>
  <li>Where AG_AGENTS.SALES_AREA_DESC = Dom. - NAT </li>
  <li>If PX_PAXWEB.COUNTRY = AUT then PX_PAXWEB.POSTCODE </li>
  <li>If PX_PAXWEB.COUNTRY &lt;> AUT then vwPxPaxweb.SALES_AREA</li>
  <li>If point 2 and/or 3 is null then just use AG_AGENTS.SALES_AREA_DESC</li>
  <li>Where AG_AGENTS.SALES_AREA_DESC = Int. – Inbound,  then vwPxPaxweb.SALES_AREA</li>
  <li><p>If point 5 is null then use AG_AGENTS.SALES_AREA_DESC</p>
  
  <pre><code>  The new field can be called as SALES_AREA_DESC_2
  </code></pre></li>
  </ol>