title: Multiple values in WHERE based on condition
body: <p>I have a input parameter, based on it I have to also include NULL and EMPTY VALUES.</p>
  <pre><code>If(TYPE=='HIGH') THEN TYPE='HIGH' OR TYPE ='' OR TYPE IS NULL
  IF(TYPE=='LOW') THEN TYPE='LOW'
  </code></pre>
  <p>Query I tried but its not working.</p>
  <pre><code>SELECT * FROM PAYRECORDS
  WHERE (TYPE =(CASE WHEN TYPE=:IP_TYPE THEN TYPE END) 
  OR TYPE IS NULL OR TYPE='')  
  </code></pre>