recover data after executing "delete " or "truncate table " in oracle

satyaki>
satyaki>
satyaki>select * from v$version;

BANNER
----------------------------------------------------------------
Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod
PL/SQL Release 10.2.0.1.0 - Production
CORE 10.2.0.1.0 Production
TNS for Linux: Version 10.2.0.1.0 - Production
NLSRTL Version 10.2.0.1.0 - Production

Elapsed: 00:00:00.02
satyaki>

satyaki>
satyaki>create table Test_SAM
2 as
3 select * from emp;

Table created.

Elapsed: 00:00:01.06
satyaki>
satyaki>
satyaki>select count(*) from Test_SAM;

COUNT(*)
----------
14

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>delete from Test_SAM;

14 rows deleted.

Elapsed: 00:00:00.00
satyaki>
satyaki>commit;

Commit complete.

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>select count(*) from Test_SAM;

COUNT(*)
----------
0

Elapsed: 00:00:00.00
satyaki>
satyaki>insert into Test_SAM
2 select *
3 from Test_SAM as of timestamp(sysdate - 1/1440);

14 rows created.

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>commit;

Commit complete.

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>select count(*) from Test_SAM;

COUNT(*)
----------
14

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>truncate table Test_SAM;

Table truncated.

Elapsed: 00:00:00.05
satyaki>
satyaki>
satyaki>select count(*) from Test_SAM;

COUNT(*)
----------
0

Elapsed: 00:00:00.00
satyaki>
satyaki>
satyaki>insert into Test_SAM
2 select *
3 from Test_SAM as of timestamp(sysdate - 1/1440);
insert into Test_SAM
*
ERROR at line 1:
ORA-01466: unable to read data - table definition has changed


Elapsed: 00:00:00.00
satyaki>