title: Filling a LOV in Oracle Apex based on data in another text box
body: <p>I am fairly new to Oracle Apex, and have a problem. Our application currently has a method of entering data, with several text boxes and Optional List of Values. I would like to have an LOV based on information in another text box like so:</p>
  
  <pre><code>select APPOINTMENT_ID PATIENT_ID from APPOINTMENT where PATIENT_ID = :P9_PAT_NUM
  </code></pre>
  
  <p>where P9_PAT_NUM is a patient number in a text box. However, this would apparently only work if the text box has already been submitted, else it assumes the text box is null.</p>
  
  <p>Is there any way to get this working with an LOV, or perhaps some other method?</p>