How to use bbed to recover data from the update

Using bbed not only retrieves data that has been delete, but also restores the update data, which is more complicated than restoring the delete data.

The experimental process is as follows:

Sys@orcl>create table Bbed_test (x int,y varchar2 (20));  
      
       
      
Table created.  
      
       
      
Sys@orcl>insert into bbed_test values (1, ' BADLY9 ');  
      
       
      
1 row created.  
      
       
      
Sys@orcl>insert into bbed_test values (2, ' JP ');  
      
       
      
1 row created.  
      
       
      
sys@orcl>commit;  
      
       
      
Commit complete. Sys@orcl>select rowID, Dbms_rowid.rowid_relative_fno (ROWID) rel_fno, 2 dbms_rowid.rowid_block_number (ROWID) b  
      
       
      
Lockno, 3 Dbms_rowid.rowid_row_number (ROWID) Rowno 4 from Bbed_test;  
      
ROWID rel_fno blockno rowno------------------------------------------------  
      
       
      
AAAM0WAABAAAOUCAAA 1 60290 0 Aaam0waabaaaoucaab 1 60290 1  
      
    Sys@orcl>update bbed_test set y= ' JP1 ' where x=1;   
      
1 row updated.  
      
       
      
sys@orcl>commit;  
      
       
      
Commit complete.  
      
       
      
Sys@orcl>select dump (1, ' ') from dual;  Dump (1, ' ')-----------------typ=2 len=2:c1,2 sys@orcl>select dump (2, ' 16 ')  
      
       
      
from dual; Dump (2, ' ')-----------------typ=2 len=2:c1,3 sys@orcl>select dump (' BADLY9  
      
       
      
', ' from dual;  
      
       
      
DUMP (' BADLY9 ',)-------------------------------typ=96 len=6:42,41,44,4c,59,39  
      
       
      
Sys@orcl>select dump (' JP1 ', ' ') from dual; DUMP (' JP1 ', ')----------------------typ=96 len=3:4a,50,31 Sys@orcl>selec  
      
       
      
         T * from Bbed_test; X Y------------------------------1 JP1 2 JP