Oracle Database Discussions

Hello,

I am facing an issue where UNDO tablespace has shot up over 95 percent quickly. I tried to find the active transactions from below query(there are no rows returned).

SELECT  *

FROM V$TRANSACTION t, V$SESSION s

WHERE t.addr = s.taddr;

When I check dba_segments and dba_free_space , I find one particular segment occupying maximum bytes.

Is there any way to identify which transaction is using that segment?

Thanks in advance.