Flashback_transaction_query.undo_sql 10g

Question

I have hard time getting over the 4000 limit on UNDO_SQL column in FLASHBACK_TRANSACTION_QUERY view on 10.2.0.3/x86 linux. The problem is in sqls longer than 4000 characters, I assume they should be split as in v$sqltext but they are not. Supplemental logging doesn't do much difference except that undo sqls are truncated and not absent.
Is there a possibility to generate UNDO_SQL for statement longer than 4000 characters at all? 11g has transaction backout based on that view so it's hard to believe that this is for small sqls only. Below example is for database without supplemental logging.
SQL> drop table t purge;
Table dropped.
SQL> create table t (x varchar2(4000), y varchar2(4000));
Table created.
SQL> insert into t values (lpad('#', 4000, '#'), lpad('#',4000, '#'));
1 row created.
SQL> commit;
Commit complete.
SQL> select max(ora_rowscn) from t;
MAX(ORA_ROWSCN)
7217362153
SQL> select undo_sql from flashback_transaction_query where commit_scn=7217362153;
UNDO_SQL
delete from "SYSTEM"."T" where ROWID = 'AAHUIxAABAAAbzLAAA';
delete from "SYSTEM"."T" where ROWID = 'AAHUIxAABAAAbzKAAA';
SQL> delete from t;
1 row deleted.
SQL> commit;
Commit complete.
SQL> select max(commit_scn) from flashback_transaction_query where table_name='T';
MAX(COMMIT_SCN)
7217364347
SQL> select undo_sql from flashback_transaction_query where commit_scn=7217364347;
UNDO_SQL
SQL> select length(undo_sql) from flashback_transaction_query where commit_scn=7217364347;
LENGTH(UNDO_SQL)
SQL> select dump(undo_sql) from flashback_transaction_query
where commit_scn=7217364347;
DUMP(UNDO_SQL)
NULL
NULL
NULL

Answer 1

Does this mean log miner (did I mention the same applies to v$logmnr_contents?), transaction backout, flashback transaction are useless for statements involving values longer than 4000 characters? Hard to believe...