Oracle 11g Flashback_transaction_query的undo_sql列为空

SQL> select table_name,operation,row_id,undo_sql
     from flashback_transaction_query where table_name='TEST'  ;
 
TABLE_NAME OPERATION  ROW_ID     UNDO_SQL
---------- ---------- ---------- --------------------------------------------------
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
 
12 rows selected
 

goole后，原来Oracle11g禁用了supplemental logging

开启后恢复正常：

SQL> alter    database     add     supplemental    log    data;
 
Database altered
 

SQL> select * from test;
 
        ID XM
---------- ----------
         1 李山
         2 杨晓

SQL> delete test where id=1;
 
1 row deleted

SQL> select table_name,operation,row_id,undo_sql
          from flashback_transaction_query where table_name='TEST';
  
 
TABLE_NAME OPERATION  ROW_ID     UNDO_SQL
---------- ---------- ---------- --------------------------------------------------
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       DELETE     AAAR9YAAFA insert into "ADMIN"."TEST"("ID","XM") values ('1',
                      AAACDAAA   '李山');
 
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
TEST       UNKNOWN               
 
13 rows selected