How to handle where xmltype has empty elements

Question

Here is my problem:
I have some information stored in table1 and some information in table2.These tables are joined with a key.
Table2 has an xmltype column. That stores if
anything (any info) has been overridden. That is has changed. There is information in this table even when nothing is overridden. In that
case the xmltype has blank elements.
In my query I have to display all records where the information has been overridden.That is fine as I extract from xmltype column using xmlsequence.
The issue arises when I need to display information when it is not overridden. In that case since the xmltype has empty
elements, the query doesnt return anything (NO RECORDS).Here it is not overridden
<?xml version="1.0" encoding="UTF-8"?>
<O><AR></AR>
</O>Here is an example where it is overridden</br>
<?xml version="1.0" encoding="UTF-8"?>
<O><AR>
     <L id="A">
          <LL>4</LL>
     </L>
     <L id="B">
          <LL>2.5</LL>
     </L>
</AR>
</O>My query is something like:
select....
,extractValue(k.column_value,'/L/@id') as lt,
extractValue(k.column_value,'/L/LL') AS ll,
FROM TABLE1 T1, TABLE2 T2,
, table(xmlsequence(T2.XMLCOL.extract('/O/AR/L')))k
WHERE ...So to tackle this problem of nothing being returned just because xmltype doesnt have overridden values, i have a query (using union to other)
that says select null for the xmltype elements that I am selecting.
I handle null as follows:
select null as lt,null as ll......
from ....This returns me a row even if something is overridden. I want a row from this null query only if it is not being returned from the other query.
I know confusing but...:-(

Answer 1

I am all set. Added something in where condition. Work around that would work:)