Flashback Query：查询过去某个时间点对象中保存的记录信息，在当前时间与指定过去某个时间点之间。
SQL> conn scott/oracle
Connected.
SQL> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
???????????????? 1196559
SQL> update flash_tbl set id=id+100 where id>15;
5 rows updated.
SQL> commit;
Commit complete.
SQL> delete flash_tbl where id<5;
4 rows deleted.
SQL> commit;
Commit complete.
SQL> desc flash_tbl
?Name????????????????????????????????????? Null???? Type
?----------------------------------------- -------- ----------------------------
?ID???????????????????????????????????????????????? NUMBER
?VL???????????????????????????????????????????????? VARCHAR2(1)
SQL> insert into flash_tbl values(300,'r');
1 row created.
SQL> insert into flash_tbl values(500,'t');
1 row created.
SQL> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
???????????????? 1196625
SQL> select id,vl,versions_startscn,versions_endscn,versions_operation,versions_xid from flash_tbl versions between scn 1196559 and 1196625;
??????? ID V VERSIONS_STARTSCN VERSIONS_ENDSCN V VERSIONS_XID
---------- - ----------------- --------------- - ----------------
?????? 120 S?????????? 1196576???????????????? U 0700290074010000
?????? 119 R?????????? 1196576???????????????? U 0700290074010000
?????? 118 Q?????????? 1196576???????????????? U 0700290074010000
?????? 117 P?????????? 1196576???????????????? U 0700290074010000
?????? 116 O?????????? 1196576???????????????? U 0700290074010000
??????? 10 I
??????? 11 J
??????? 12 K
??????? 13 L
??????? 14 M
??????? 15 N
??????? ID V VERSIONS_STARTSCN VERSIONS_ENDSCN V VERSIONS_XID
---------- - ----------------- --------------- - ----------------
??????? 16 O?????????????????????????? 1196576
??????? 17 P?????????????????????????? 1196576
??????? 18 Q?????????????????????????? 1196576
??????? 19 R?????????????????????????? 1196576
??????? 20 S?????????????????????????? 1196576
???????? 4 C?????????? 1196588???????????????? D 08000B0096010000
???????? 3 B?????????? 1196588???????????????? D 08000B0096010000
???????? 2 A?????????? 1196588???????????????? D 08000B0096010000
???????? 1 /?????????? 1196588???????????????? D 08000B0096010000
???????? 1 /?????????????????????????? 1196588
???????? 2 A?????????????????????????? 1196588
??????? ID V VERSIONS_STARTSCN VERSIONS_ENDSCN V VERSIONS_XID
---------- - ----------------- --------------- - ----------------
???????? 3 B?????????????????????????? 1196588
???????? 4 C?????????????????????????? 1196588
???????? 5 D
???????? 6 E
???????? 7 F
???????? 8 G
???????? 9 H
29 rows selected.
??
根据记录，可以看到开始SCN和结束SCN，从操作列有I（插入），U（更新），D（删除），还有事务ID。
SQL> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
???????????????? 1200548
SQL> delete flash_tbl where id=116;
1 row deleted.
SQL> commit;
Commit complete.
SQL> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
???????????????? 1200555
SQL> conn / as sysdba
Connected.
SQL> grant select any transaction to scott;
Grant succeeded.
SQL> conn scott/oracle
Connected.
SQL> select xid,commit_scn,commit_timestamp,operation,undo_sql from flashback_transaction_query Q where Q.xid in(select versions_xid from flash_tbl versions between
scn 1200548 and 1200555);
XID????????????? COMMIT_SCN COMMIT_TI OPERATION
---------------- ---------- --------- --------------------------------
UNDO_SQL
--------------------------------------------------------------------------------
0A002F0062010000??? 1200554 31-MAR-14 DELETE
insert into "SCOTT"."FLASH_TBL"("ID","VL") values ('116','O');
0A002F0062010000??? 1200554 31-MAR-14 BEGIN
?通过上面可以看到，刚才所做的操作及时间，与LogMiner功能挺像。
