title: Dropdown list validation based on another field's value in SQL
body: <p>I currently have the following 4 tables:</p>
  
  <p><strong>Contacts</strong></p>
  
  <pre><code>Contact_ID,
  ContactName
  </code></pre>
  
  <p><strong>Roles</strong></p>
  
  <pre><code>Role_ID,
  Role
  </code></pre>
  
  <p><strong>Contact Roles</strong></p>
  
  <pre><code>ContactRole_ID,
  Contact_ID,
  Role_ID
  </code></pre>
  
  <p><strong>Events - Contacts</strong></p>
  
  <pre><code>EventContact_ID
  Contact_ID
  ContactRole_ID
  </code></pre>
  
  <p>My end goal is to limit the value that can be selected in the <code>ContactRole_ID</code> field of the <strong>Events - Contacts</strong> table based on the value selected in the <code>Contact_ID</code> field so that only Roles that the Contact is associated with will show up as options.  Is there a way to do that using SQL?</p>
  
  <p>If any additional information or clarification is needed, please let me know. Thank you in advance for any help.</p>