saup007

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[物理/逻辑坏块] 闪回一点疑问--flashback database后resetlogs，还能否向前闪回

1^#

发表于 2013-1-17 17:16:23 | 查看: 3902| 回复: 2

都在说flashback database 后，以resetlogs打开数据库后，不能向前闪回，只能往后闪回

实验如下：

注意，一旦resetlogs之后，将不能再flashback至resetlogs之前的时间点
我这个实验，好像可以，但如果涉及之后有表空间创建或数据文件添加。估计就不行了。

这是昨天的操作，和时间

17:47:09 sys@TEST10G> create tablespace test_flashback datafile '/u01/oradata/TEST10G/test_flashback.dbf' size 1M ;

Tablespace created.

17:48:59 sys@TEST10G> create table saup.flashback_recover1 tablespace test_flashback as select * from dba_objects where rownum<8000;

Table created.

这是今天的操作和时间

16:31:03 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 18:00:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:31:46 sys@TEST10G> alter database open resetlogs;
Database altered.
16:32:17 sys@TEST10G> shutdown immediate;
16:32:49 sys@TEST10G> startup mount
16:32:57 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 20:00:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:33:12 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 17:00:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:33:59 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 16:30:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:34:10 sys@TEST10G>
16:34:10 sys@TEST10G> alter database open resetlogs;
Database altered.
16:34:26 sys@TEST10G> select CREATED,RESETLOGS_CHANGE#,RESETLOGS_TIME from v$database;
CREATED RESETLOGS_CHANGE# RESETLOGS_TIME
------------------- ----------------- -------------------
2013-01-16 16:03:01 616073 2013-01-17 16:34:24
16:34:48 sys@TEST10G> shutdown immediate;
16:35:18 sys@TEST10G> startup mount
16:35:47 sys@TEST10G> select * from v$flashback_database_log;
OLDEST_FLASHBACK_SCN OLDEST_FLASHBACK_TI RETENTION_TARGET FLASHBACK_SIZE ESTIMATED_FLASHBACK_SIZE
-------------------- ------------------- ---------------- -------------- ------------------------
615690 2013-01-16 16:23:23 1440 36864000 0
16:36:13 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 16:25:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:36:46 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 17:25:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:37:10 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 16:25:00','yyyy-mm-dd hh24:mi:ss');
Flashback complete.
16:37:22 sys@TEST10G> flashback database to timestamp to_timestamp('2013-01-16 18:25:00','yyyy-mm-dd hh24:mi:ss');
flashback database to timestamp to_timestamp('2013-01-16 18:25:00','yyyy-mm-dd hh24:mi:ss')
*
ERROR at line 1:
ORA-38795: warning: FLASHBACK succeeded but OPEN RESETLOGS would get error below
ORA-01245: offline file 6 will be lost if RESETLOGS is done
ORA-01111: name for data file 6 is unknown - rename to correct file
ORA-01110: data file 6: '/u01/app/oracle/product/10.2.0/test_10g/dbs/UNNAMED00006'
16:37:31 sys@TEST10G>
16:38:00 sys@TEST10G>
16:38:00 sys@TEST10G> flashback database to scn 621452;
flashback database to scn 621452
*
ERROR at line 1:
ORA-38795: warning: FLASHBACK succeeded but OPEN RESETLOGS would get error below
ORA-01245: offline file 6 will be lost if RESETLOGS is done
ORA-01111: name for data file 6 is unknown - rename to correct file
ORA-01110: data file 6: '/u01/app/oracle/product/10.2.0/test_10g/dbs/UNNAMED00006'