title: Oracle trigger multiple conditions in when clause
body: <p>I'm trying to create a trigger that updates a column in a table when other columns are updated. but getting the following error while saving the trigger</p>
  <p><code>ORA-25000: invalid use of bind variable in trigger WHEN clause</code></p>
  <p>My trigger is as follows, I'm not sure what is wrong with the code.</p>
  <pre><code>CREATE OR REPLACE TRIGGER  Employees_ARIU 
  BEFORE  INSERT OR  UPDATE ON Employees 
  FOR EACH ROW
  WHEN ((nvl(:OLD.EMP_SAL,0) != nvl(:NEW.EMP_SAL,0)) OR (nvl(:OLD.SAL_LEVEL,0) != nvl(:NEW.SAL_LEVEL,0)))
  BEGIN
          :NEW.LAST_UPDATED = SYSDATE
  END;
  </code></pre>