Oracle Study学习之--Flashback Archive

CREATE FLASHBACK ARCHIVE

Purpose

Use the CREATE FLASHBACK ARCHIVE statement tocreate a flashback data archive, which provides the ability to automaticallytrack and archive transactional data changes to specified database objects. Aflashback data archive consists of multiple tablespaces and stores historicdata from all transactions against tracked tables.

Flashback dataarchives retain historical data for the time duration specified using the RETENTION parameter.Historical data can be queried using the Flashback Query AS OF clause.Archived historic data that has aged beyond the specified retention period isautomatically purged.

Flashback dataarchives retain historical data across data definition language (DDL) changesto tables enabled for flashback data archive. Flashback data archives supportsa lot of common DDL statements, including some DDL statements that alter tabledefinitions or incur data movement. DDL statements that are not supportedresult in error ORA-55610.

Syntax

create_flashback_archive::=

一、     建立flashbackarchive

1、建立flashback专用表空间

14:33:13 [email protected] orcl >create tablespaceflash_tbs

14:33:26  2  datafile‘/u01/app/oracle/oradata/orcl/flash_tbs01.dbf‘ size 100m;

Tablespace created.

Elapsed: 00:00:22.03

2、建立flashback archive

14:36:16 [email protected] orcl >create flashbackarchive farch1

14:36:54  2  tablespace flash_tbs

14:36:58  3  quota 20m

14:37:01  4  retention 1 month;

Flashback archive created.

3、修改flashback archive属性

14:37:09 [email protected] orcl >alter flashbackarchive farch1 set default;

Flashback archive altered.

Elapsed: 00:00:00.15

4、查看flashback archive属性

14:40:13 [email protected] orcl >colFLASHBACK_ARCHIVE_NAME for a20

14:40:25 [email protected] orcl >select FLASHBACK_ARCHIVE_NAME,RETENTION_IN_DAYS ,STATUS fromdba_flashback_archive;

FLASHBACK_ARCHIVE_NA RETENTION_IN_DAYSSTATUS

-------------------- ------------------------

FARCH1                              30 DEFAULT

Elapsed: 00:00:00.01

14:41:54 [email protected] orcl >col QUOTA_IN_MB fora10

14:42:02 [email protected] orcl >select * from dba_flashback_archive_ts;

FLASHBACK_ARCHIVE_NA FLASHBACK_ARCHIVE# TABLESPACE_NAME                QUOTA_IN_M

-------------------- ------------------------------------------------ ----------

FARCH1                                1FLASH_TBS                      20

5、添加tablespace到flashback archive

14:42:03 [email protected] orcl >create tablespaceflash_tbs2

14:42:36  2  datafile‘/u01/app/oracle/oradata/orcl/flash_tbs2a.dbf‘ size 100m;

Tablespace created.

14:43:51 [email protected] orcl >alter flashbackarchive farch1 add tablespace flash_tbs2;

Flashback archive altered.

Elapsed: 00:00:00.22

14:44:05 [email protected] orcl >select * fromdba_flashback_archive_ts;

FLASHBACK_ARCHIVE_NA FLASHBACK_ARCHIVE#TABLESPACE_NAME                QUOTA_IN_M

-------------------- ------------------------------------------------ ----------

FARCH1                                1 FLASH_TBS                      20

FARCH1                                1 FLASH_TBS2

Elapsed: 00:00:00.00

二、在表上启用flashbackarchive

1、授予权限

15:00:11 [email protected] orcl >select * fromsystem_privilege_map where NAME like ‘%FLASHBACK%‘;

PRIVILEGE NAME                                       PROPERTY

-------------------------------------------------- ----------

-243 FLASHBACK ANY TABLE                               0

-350 FLASHBACK ARCHIVE ADMINISTER                      0

Elapsed: 00:00:00.03

15:00:38 [email protected] orcl >grant flashbackarchive on farch1 to scott;

Grant succeeded.

15:04:50 [email protected] orcl >alter table emp2flashback archive;

Table altered.

15:11:13 [email protected] orcl >select * from tab;

TNAME                          TABTYPE  CLUSTERID

------------------------------ -----------------

BONUS                          TABLE

DEPT                           TABLE

DEPT1                          TABLE

EMP                           TABLE

EMP1                           TABLE

EMP2                           TABLE

EMP3                           TABLE

SALGRADE                       TABLE

SYS_FBA_DDL_COLMAP_75889       TABLE

SYS_FBA_HIST_75889             TABLE

SYS_FBA_TCRV_75889             TABLE

三、     flashback archive 应用

1）   访问历史数据

15:09:[email protected] orcl >set autotrace on

15:09:[email protected] orcl >r

1* select * from emp2 as of timestampto_timestamp(‘2015-05-11 15:05:04‘,‘yyyy-mm-dd hh24:mi:ss‘)

EMPNO ENAME      JOB             MGR HIREDATE            SAL       COMM    DEPTNO

-------------------- --------- ---------- ------------ ---------- ---------- ----------

7566 JONES      MANAGER         7839 02-APR-81          2975                    20

7900 JAMES      CLERK           7698 03-DEC-81           950                    30

7698 BLAKE      MANAGER         7839 01-MAY-81          2850                    30

7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30

7839 KING       PRESIDENT            17-NOV-81          5000                    10

7844 TURNER     SALESMAN        7698 08-SEP-81          1500          0         30

7902 FORD       ANALYST         7566 03-DEC-81          3000                    20

7654 MARTIN     SALESMAN        7698 28-SEP-81          1250       1400         30

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

7782 CLARK      MANAGER         7839 09-JUN-81          2450                    10

7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30

7934 MILLER     CLERK           7782 23-JAN-82          1300                    10

7369 SMITH      CLERK           7902 17-DEC-80           800                    20

7876 ADAMS      CLERK           7788 23-MAY-87          1100                    20

14 rowsselected.

Elapsed:00:00:00.03

ExecutionPlan

----------------------------------------------------------

Plan hashvalue: 3389285906

----------------------------------------------------------------------------------------------------------------

| Id  | Operation                 | Name               | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |

----------------------------------------------------------------------------------------------------------------

|   0 | SELECT STATEMENT          |                    |    17 | 1479 |    11  (10)| 00:00:01 |       |      |

|   1 | VIEW                     |                    |   17 |  1479 |    11 (10)| 00:00:01 |       |       |

|   2 |  UNION-ALL               |                    |       |      |            |          |       |      |

|*  3 |   FILTER                 |                    |       |      |            |         |       |       |

|   4 |    PARTITION RANGE SINGLE|                    |     1 |  113 |     2   (0)| 00:00:01 |   KEY |    1 |

|*  5 |     TABLE ACCESS FULL    |SYS_FBA_HIST_75889 |     1 |   113 |    2   (0)| 00:00:01 |   KEY |    1 |

|*  6 |   FILTER                 |                    |       |      |            |          |       |      |

|*  7 |    HASH JOIN OUTER       |                    |    16 | 34032 |     9 (12)| 00:00:01 |       |       |

|*  8 |     TABLE ACCESS FULL    | EMP2               |    16 | 1584 |     5   (0)| 00:00:01 |       |      |

|*  9 |     TABLE ACCESS FULL    |SYS_FBA_TCRV_75889 |     4 |  8112 |    3   (0)| 00:00:01 |       |      |

----------------------------------------------------------------------------------------------------------------

PredicateInformation (identified by operation id):

---------------------------------------------------

3 -filter("TIMESTAMP_TO_SCN"(TIMESTAMP‘ 2015-05-1115:05:04.000000000‘)<10456170)

5 - filter("ENDSCN"<=10456170AND "ENDSCN">"TIMESTAMP_TO_SCN"(TIMESTAMP‘ 2015-05-11

15:05:04.000000000‘) AND("STARTSCN" IS NULL OR "STARTSCN"<="TIMESTAMP_TO_SCN"(TIMESTAMP‘2015-05-11

15:05:04.000000000‘)))

6 -filter("STARTSCN"<="TIMESTAMP_TO_SCN"(TIMESTAMP‘2015-05-11 15:05:04.000000000‘) OR "STARTSCN"

IS NULL)

7 -access("T".ROWID=CHARTOROWID("RID"(+)))

8 -filter("T"."VERSIONS_STARTSCN" IS NULL)

9 - filter(("ENDSCN"(+) IS NULL OR"ENDSCN"(+)>10456170) AND ("STARTSCN"(+) IS NULL OR

"STARTSCN"(+)<10456170))

Note

-----

- dynamic sampling used for this statement(level=2)

Statistics

----------------------------------------------------------

78 recursive calls

0 db block gets

111 consistent gets

0 physical reads

0 redo size

1421 bytes sent via SQL*Net to client

415 bytes received via SQL*Net from client

2 SQL*Net roundtrips to/from client

3 sorts (memory)

0 sorts (disk)

14 rows processed

15:09:11 [email protected] orcl >

2）   生成统计报表

15:12:[email protected] orcl >select * from emp2

15:14:53   2  versions

15:14:57   3 between timestamp

15:15:16   4 to_timestamp(‘2015-05-11 15:05:04‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:15:29   5  andmaxvalue

15:15:34   6 where ename=‘SCOTT‘;

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM    DEPTNO

-------------------- --------- ---------- ------------ ---------- ---------- ----------

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

Elapsed:00:00:00.01

15:15:45 [email protected] orcl >

3）   信息生命周期管理

15:15:[email protected] orcl >select count(*) from emp2;

COUNT(*)

----------

18

Elapsed:00:00:00.00

15:17:[email protected] orcl >insert into emp2 select * from emp2;

18 rowscreated.

Elapsed:00:00:00.00

15:17:[email protected] orcl >commit;

Commit complete.

Elapsed:00:00:00.09

15:17:[email protected] orcl >select count(*) from emp2;

COUNT(*)

----------

36

Elapsed:00:00:00.00

15:17:[email protected] orcl >select * from emp2

15:18:00   2        versions

15:18:06   3   between timestamp

15:18:13   4   to_timestamp(‘2015-05-11 15:05:04‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:18:30   5   and

15:18:32   6   to_timestamp(‘2015-05-11 15:17:33‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:19:06   7   where empno=7788;

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM    DEPTNO

-------------------- --------- ---------- ------------ ---------- ---------- ----------

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

Elapsed:00:00:00.00

15:19:[email protected] orcl >select * from emp2 where empno=7788;

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM    DEPTNO

-------------------- --------- ---------- ------------ ---------- ---------- ----------

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

Elapsed:00:00:00.00

15:19:[email protected] orcl >select * from emp2

15:19:42   2 versions

15:19:45   3 between timestamp

15:19:48   4  to_timestamp(‘2015-05-0915:05:04‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:19:59   5  and

15:20:02   6 to_timestamp(‘2015-05-11 15:17:33‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:20:06   7 where empno=7788;

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM    DEPTNO

-------------------- --------- ---------- ------------ ---------- ---------- ----------

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

Elapsed:00:00:00.02

15:20:[email protected] orcl >select * from emp2

15:20:27   2 versions

15:20:30   3 between timestamp

15:20:37   4 to_timestamp(‘2015-05-09 15:05:04‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:20:41   5  and

15:20:44   6 to_timestamp(‘2015-05-11 15:20:00‘,‘yyyy-mm-dd hh24:mi:ss‘)

15:21:01   7 where empno=7788;

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM    DEPTNO

-------------------- --------- ---------- ------------ ---------- ---------- ----------

7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20

Elapsed:00:00:00.01

案例测试：

flashback archive：

1、建立flashback archive 专用tablespace

11:15:32 [email protected] orcl >create tablespace ftbs1
11:15:40   2  datafile ‘/u01/app/oracle/oradata/orcl/ftbs1.dbf‘ size 100m;

Tablespace created.
Elapsed: 00:00:25.14

2、建立flashback archive
11:16:17 [email protected] orcl >create flashback archive farch1
11:16:41   2  tablespace ftbs1
11:17:14   3  quota 20m
11:17:26   4  retention 7 day;

Flashback archive created.
Elapsed: 00:00:00.28

3、查询属性
11:17:49 [email protected] orcl >select FLASHBACK_ARCHIVE_NAME,RETENTION_IN_DAYS ,STATUS from dba_flashback_archive
11:18:07   2  ;

FLASHBACK_ RETENTION_IN_DAYS STATUS
---------- ----------------- -------
FARCH1                     7

Elapsed: 00:00:00.01
11:18:08 [email protected] orcl >select * from dba_flashback_archive_ts;

FLASHBACK_ FLASHBACK_ARCHIVE# TABLESPACE_NAME                QUOTA_IN_M
---------- ------------------ ------------------------------ ----------
FARCH1                      1 FTBS1                          20

Elapsed: 00:00:00.01


11:18:37 [email protected] orcl >alter flashback archive farch1 set default;
Flashback archive altered.
Elapsed: 00:00:00.19


11:18:56 [email protected] orcl >select FLASHBACK_ARCHIVE_NAME,RETENTION_IN_DAYS ,STATUS from dba_flashback_archive;

FLASHBACK_ RETENTION_IN_DAYS STATUS
---------- ----------------- -------
FARCH1                     7 DEFAULT

Elapsed: 00:00:00.01

4、授权用户在table启用flashback archive
11:19:11 [email protected] orcl >grant flashback archive on farch1 to scott;
Grant succeeded.

11:20:56 [email protected] orcl >alter table emp2 flashback archive farch1;
Table altered.
Elapsed: 00:00:00.31


11:21:14 [email protected] orcl >select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
BONUS                          TABLE
DEPT                           TABLE
EMP                            TABLE
EMP2                           TABLE
SALGRADE                       TABLE
T1                             TABLE
6 rows selected.
Elapsed: 00:00:00.01


11:21:46 [email protected] orcl >delete from emp2;
36 rows deleted.
Elapsed: 00:00:00.03


11:22:05 [email protected] orcl >commit;
Commit complete.
Elapsed: 00:00:00.19


11:22:08 [email protected] orcl >select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
BONUS                          TABLE
DEPT                           TABLE
EMP                            TABLE
EMP2                           TABLE
SALGRADE                       TABLE
T1                             TABLE
6 rows selected.
Elapsed: 00:00:00.00


11:22:12 [email protected] orcl >select * from emp2;
no rows selected
Elapsed: 00:00:00.00

4、查询flashback archive数据

默认，Oracle 优先从undo block读取历史数据，若undo block数据不存在，然后再去访问 flashback archive。
11:24:06 [email protected] orcl >set autotrace on
11:24:16 [email protected] orcl >select * from emp2 as of timestamp to_timestamp(‘2015-05-12 11:21:46‘,‘yyyy-mm-dd hh24:mi:ss‘);

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM     DEPTNO
---------- ---------- --------- ---------- ------------ ---------- ---------- ----------
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
      7654 MARTIN     SALESMAN        7698 28-SEP-81          1250       1400         30
      7698 BLAKE      MANAGER         7839 01-MAY-81          2850                    30
      7782 CLARK      MANAGER         7839 09-JUN-81          2450                    10
      7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20
      7839 KING       PRESIDENT            17-NOV-81          5000                    10
      7844 TURNER     SALESMAN        7698 08-SEP-81          1500          0         30
      7876 ADAMS      CLERK           7788 23-MAY-87          1100                    20
      7900 JAMES      CLERK           7698 03-DEC-81           950                    30
      7902 FORD       ANALYST         7566 03-DEC-81          3000                    20
      7934 MILLER     CLERK           7782 23-JAN-82          1300                    10
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM     DEPTNO
---------- ---------- --------- ---------- ------------ ---------- ---------- ----------
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
      7654 MARTIN     SALESMAN        7698 28-SEP-81          1250       1400         30
      7698 BLAKE      MANAGER         7839 01-MAY-81          2850                    30
      7782 CLARK      MANAGER         7839 09-JUN-81          2450                    10
      7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20
      7839 KING       PRESIDENT            17-NOV-81          5000                    10
      7844 TURNER     SALESMAN        7698 08-SEP-81          1500          0         30
      7876 ADAMS      CLERK           7788 23-MAY-87          1100                    20
      7900 JAMES      CLERK           7698 03-DEC-81           950                    30
      7902 FORD       ANALYST         7566 03-DEC-81          3000                    20
      7934 MILLER     CLERK           7782 23-JAN-82          1300                    10
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM     DEPTNO
---------- ---------- --------- ---------- ------------ ---------- ---------- ----------
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
36 rows selected.
Elapsed: 00:00:00.01

Execution Plan
----------------------------------------------------------
Plan hash value: 2941272003

--------------------------------------------------------------------------
| Id  | Operation         | Name | Rows  | Bytes | Cost (%CPU)| Time     |
--------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |      |   654 | 56898 |     9   (0)| 00:00:01 |
|   1 |  TABLE ACCESS FULL| EMP2 |   654 | 56898 |     9   (0)| 00:00:01 |
--------------------------------------------------------------------------
Statistics
----------------------------------------------------------
          4  recursive calls
          0  db block gets
         10  consistent gets
          0  physical reads
          0  redo size
       2655  bytes sent via SQL*Net to client
        437  bytes received via SQL*Net from client
          4  SQL*Net roundtrips to/from client
          0  sorts (memory)
          0  sorts (disk)
         36  rows processed
         
         
         从以上sql可以看到，数据是从undo data读出

11:25:16 [email protected] orcl >set autotrace off
11:25:23 [email protected] orcl >select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
BONUS                          TABLE
DEPT                           TABLE
EMP                            TABLE
EMP2                           TABLE
SALGRADE                       TABLE
SYS_FBA_DDL_COLMAP_75889       TABLE
SYS_FBA_HIST_75889             TABLE
SYS_FBA_TCRV_75889             TABLE
T1                             TABLE
9 rows selected.
Elapsed: 00:00:00.01


6、建立新的undo tablespace，然后切换
11:19:42 [email protected] orcl >create undo tablespace undotbs1
11:25:57   2  datafile ‘/u01/app/oracle/oradata/orcl/undotbs1.dbf‘ size 100m;
Tablespace created.
Elapsed: 00:00:23.73


11:26:41 [email protected] orcl >show parameter undo

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
undo_management                      string      AUTO
undo_retention                       integer     3600
undo_tablespace                      string      UNDOTBS2
11:26:45 [email protected] orcl >alter system set undo_tablespace=undotbs1;
System altered.
Elapsed: 00:00:00.27


重新启动数据库：
11:27:20 [email protected] orcl >startup force;
ORACLE instance started.

Total System Global Area  205049856 bytes
Fixed Size                  1335500 bytes
Variable Size             113250100 bytes
Database Buffers           88080384 bytes
Redo Buffers                2383872 bytes
Database mounted.
Database opened.

再次查询历史数据，因为切换undo tablespace，以前的undo block不能访问，所以会从flashback archive读取数据
11:27:50 @  >conn scott/tiger
Connected.
11:27:58 [email protected] orcl >set autotrace on
11:28:02 [email protected] orcl >select * from emp2 as of timestamp to_timestamp(‘2015-05-12 11:21:46‘,‘yyyy-mm-dd hh24:mi:ss‘);

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM     DEPTNO
---------- ---------- --------- ---------- ------------ ---------- ---------- ----------
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
      7654 MARTIN     SALESMAN        7698 28-SEP-81          1250       1400         30
      7698 BLAKE      MANAGER         7839 01-MAY-81          2850                    30
      7782 CLARK      MANAGER         7839 09-JUN-81          2450                    10
      7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20
      7839 KING       PRESIDENT            17-NOV-81          5000                    10
      7844 TURNER     SALESMAN        7698 08-SEP-81          1500          0         30
      7876 ADAMS      CLERK           7788 23-MAY-87          1100                    20
      7900 JAMES      CLERK           7698 03-DEC-81           950                    30
      7902 FORD       ANALYST         7566 03-DEC-81          3000                    20
      7934 MILLER     CLERK           7782 23-JAN-82          1300                    10
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM     DEPTNO
---------- ---------- --------- ---------- ------------ ---------- ---------- ----------
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
      7654 MARTIN     SALESMAN        7698 28-SEP-81          1250       1400         30
      7698 BLAKE      MANAGER         7839 01-MAY-81          2850                    30
      7782 CLARK      MANAGER         7839 09-JUN-81          2450                    10
      7788 SCOTT      ANALYST         7566 19-APR-87          3000                    20
      7839 KING       PRESIDENT            17-NOV-81          5000                    10
      7844 TURNER     SALESMAN        7698 08-SEP-81          1500          0         30
      7876 ADAMS      CLERK           7788 23-MAY-87          1100                    20
      7900 JAMES      CLERK           7698 03-DEC-81           950                    30
      7902 FORD       ANALYST         7566 03-DEC-81          3000                    20
      7934 MILLER     CLERK           7782 23-JAN-82          1300                    10
      7369 SMITH      CLERK           7902 17-DEC-80           800                    20
      7499 ALLEN      SALESMAN        7698 20-FEB-81          1600        300         30

EMPNO ENAME      JOB              MGR HIREDATE            SAL       COMM     DEPTNO
---------- ---------- --------- ---------- ------------ ---------- ---------- ----------
      7521 WARD       SALESMAN        7698 22-FEB-81          1250        500         30
      7566 JONES      MANAGER         7839 02-APR-81          2975                    20
36 rows selected.
Elapsed: 00:00:00.13

Execution Plan
----------------------------------------------------------
Plan hash value: 3389285906

----------------------------------------------------------------------------------------------------------------
| Id  | Operation                 | Name               | Rows  | Bytes | Cost (%CPU)| Time     | Pstart| Pstop |
----------------------------------------------------------------------------------------------------------------
|   0 | SELECT STATEMENT          |                    |    34 |  2958 |    16   (7)| 00:00:01 |       |       |
|   1 |  VIEW                     |                    |    34 |  2958 |    16   (7)| 00:00:01 |       |       |
|   2 |   UNION-ALL               |                    |       |       |            |          |       |       |
|*  3 |    FILTER                 |                    |       |       |            |          |       |       |
|   4 |     PARTITION RANGE SINGLE|                    |     1 |   113 |     3   (0)| 00:00:01 |   KEY |     1 |
|*  5 |      TABLE ACCESS FULL    | SYS_FBA_HIST_75889 |     1 |   113 |     3   (0)| 00:00:01 |   KEY |     1 |
|*  6 |    FILTER                 |                    |       |       |            |          |       |       |
|*  7 |     HASH JOIN OUTER       |                    |    33 | 70191 |    13   (8)| 00:00:01 |       |       |
|*  8 |      TABLE ACCESS FULL    | EMP2               |    33 |  3267 |     9   (0)| 00:00:01 |       |       |
|*  9 |      TABLE ACCESS FULL    | SYS_FBA_TCRV_75889 |    36 | 73008 |     3   (0)| 00:00:01 |       |       |
----------------------------------------------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

3 - filter("TIMESTAMP_TO_SCN"(TIMESTAMP‘ 2015-05-12 11:21:46.000000000‘)<10558115)
   5 - filter("ENDSCN"<=10558115 AND "ENDSCN">"TIMESTAMP_TO_SCN"(TIMESTAMP‘ 2015-05-12
              11:21:46.000000000‘) AND ("STARTSCN" IS NULL OR "STARTSCN"<="TIMESTAMP_TO_SCN"(TIMESTAMP‘ 2015-05-12
              11:21:46.000000000‘)))
   6 - filter("STARTSCN"<="TIMESTAMP_TO_SCN"(TIMESTAMP‘ 2015-05-12 11:21:46.000000000‘) OR "STARTSCN"
              IS NULL)
   7 - access("T".ROWID=CHARTOROWID("RID"(+)))
   8 - filter("T"."VERSIONS_STARTSCN" IS NULL)
   9 - filter(("ENDSCN"(+) IS NULL OR "ENDSCN"(+)>10558115) AND ("STARTSCN"(+) IS NULL OR
              "STARTSCN"(+)<10558115))

Note
-----
   - dynamic sampling used for this statement (level=2)

Statistics
----------------------------------------------------------
       3280  recursive calls
          0  db block gets
        852  consistent gets
        202  physical reads
        412  redo size
       2489  bytes sent via SQL*Net to client
        437  bytes received via SQL*Net from client
          4  SQL*Net roundtrips to/from client
         57  sorts (memory)
          0  sorts (disk)
         36  rows processed
         
         从以上执行计划可以看出，访问的是flashback archive ，而不是undo data。

时间： 2024-08-15 13:42:44

Oracle Study学习之--Flashback Archive的相关文章

Oracle Study之案例--数据恢复神器Flashback（1）

Oracle Study之案例--数据恢复神器Flashback(1) Flashback: Flashback 技术是以Undo segment中的内容为基础的, 因此受限于UNDO_RETENTON参数.要使用flashback 的特性,必须启用自动撤销管理表空间. 在Oracle 11g里又出了一个新特性:Oracle Flashback Data Archive. FDA通过将变化数据另外存储到创建的闪回归档区(Flashback Archive)中,以和undo区别开来,这样就可以为闪

Oracle Study之案例--Oracle 11g DataGuard Snapshot Standby

Oracle Study之案例--Oracle 11g  DataGuard Snapshot Standby Oracle 11g的Data Guard不仅仅带给我们的是Active Data Guard实时查询特性,同时还带来了另外一个新特性,这便是Snapshot Standby数据库功能,此项功能可将备库置身于"可读写状态"用于不方便在生产环境主库中测试的内容,比如模拟上线测试等任务.当备库读写状态下任务完成后,可以非常轻松的完成Snapshot Standby数据库角色切换回

MySQl Study学习之--MySQl二进制日志管理

MySQl Study学习之--MySQl二进制日志管理 MySQL二进制日志(Binary Log):   a.它包含的内容及作用如下:    包含了所有更新了数据或者已经潜在更新了数据(比如没有匹配任何行的一个DELETE)    包含关于每个更新数据库(DML)的语句的执行时间信息    不包含没有修改任何数据的语句,如果需要启用该选项,需要开启通用日志功能    主要目的是尽可能的将数据库恢复到数据库故障点,因为二进制日志包含备份后进行的所有更新    用于在主复制服务器上记录所有将发送

Oracle Study之--Oracle 11gR2通过RMAN克隆数据库

Oracle Study之--Oracle 11gR2通过RMAN克隆数据库 Purpose of Database Duplication A duplicate database is useful for a variety of purposes, most of which involve testing. You can perform the following tasks in a duplicate database: Test backup and recovery proc

Oracle Study之--AMD CPU安装Oracle 11gR2 RAC错误

Oracle Study之--AMD CPU安装Oracle 11gR2 RAC错误 系统环境: 操作系统: RedHat  EL55     Oracle :     Oracle 11gR2 Grid +  Oracle 1.错误现象 [[email protected] install]# /u01/11.2.0/grid/root.shRunning Oracle 11g root.sh script... The following environment variables are 

Oracle Study之--DBCA建库错误

Oracle Study之--DBCA建库错误 系统环境: 操作系统: RedHat EL54 Oracle :   Oracle 11gR2 故障现象: 在安装好11gR2软件后准备通过dbca创建数据库,执行dbca的时候包如下错误: [[email protected] ~]$ dbcaOracle Net Services Configuration: ## An unexpected error has been detected by HotSpot Virtual Machine:

Oracle GoldenGate学习之--基本概念和配置

Oracle GoldenGate学习之--基本概念和配置(1) 一  GoldenGate简介 Oracle Golden Gate软件是一种基于日志的结构化数据复制备份软件,它通过解析源 数据库在线日志或归档日志获得数据的增量变化,再将这些变化应用到目标数据库,从而实现源数据库与目标数据库同步.Oracle Golden Gate可以在异构的IT基础结构(包括几乎 所有常用操作系统平台和数据库平台)之间实现大量数据亚秒一级的实时复制,从而在可以 在应急系统.在线报表.实时数据仓库供应.交易跟

Oracle GoldenGate学习之--AIX rac系统安装配置（1）

Oracle GoldenGate学习之--AIX rac系统安装配置(1) 系统环境 操作系统:AIX5.3-09 DB Soft:  Oracle 10gR2 Cluster:   CRS 10.2.0.1 如下图所示: 本案例是用于基于VG Concurrent 的共享存储: 系统环境实在AIX系统上构建的Oracle RAC 下载OGG: http://www.oracle.com/technetwork/cn/middleware/goldengate/downloads/index.

转：Oracle GoldenGate学习之Goldengate介绍

转自:http://blog.sina.com.cn/s/blog_a32eff28010136d9.html 日志或归档日志获得数据的增删改变化,再将这些变化应用到目标数据库,实现源数据库与目标数据库同步.双活.GoldenGate TDM 软件可以在异构的IT基础结构(包括几乎所有常用操作系统平台和数据库平台)之间实现大量数据亚秒一级的实时复制,其复制过程简图如下: 如上图所示,GoldenGate TDM的数据复制过程如下: 利用捕捉进程(Capture Process)在源系统端读取On