%s: 日志序列号 %S: 日志序列号(带有前导0) %t: 重做线程编号.%T: 重做线程编号(带有前导0) %a: 活动ID %d: 数据库ID号 %r RESETLOGS的值.
SYS@bys1>select * from (select name,recid,sequence#,status,applied from v$archived_log order by recid desc) where rownum<5;
NAME RECID SEQUENCE# S APPLIED
---------------------------------------- ---------- ---------- - ---------
/u01/archbys1/arc_1_32_829941492.arc 121 32 A NO 这里忘了手动做一次归档，所以看不出归档日志名中日志序列号被重置为1
120 31 D NO
119 30 D NO
118 29 D NO
SYS@bys1>select dbid,checkpoint_change# from v$database;
DBID CHECKPOINT_CHANGE#
---------- ------------------
3957527513 3228987
SYS@bys1>select file#,name,checkpoint_change#,to_char(checkpoint_time,'yyyy-mm-dd hh24:mi:ss') cptime from v$datafile;
FILE# NAME CHECKPOINT_CHANGE# CPTIME
---------- ---------------------------------------- ------------------ -------------------
1 /u01/oradata/bys1/system01.dbf 32289872013-11-06 00:14:27
2 /u01/oradata/bys1/sysaux01.dbf 3228987 2013-11-06 00:14:27
3 /u01/oradata/bys1/undotbs01.dbf 3228987 2013-11-06 00:14:27
4 /u01/oradata/bys1/users01.dbf 3228987 2013-11-06 00:14:27
5 /u01/oradata/bys1/example01.dbf 3228987 2013-11-06 00:14:27
6 /u01/oradata/bys1/test1.dbf 3228987 2013-11-06 00:14:27
SYS@bys1>select GROUP#,sequence#,STATUS,FIRST_CHANGE#,to_char(FIRST_TIME,'yyyy/mm/dd:hh24:mi:ss') time from V$log;
GROUP# SEQUENCE# STATUS FIRST_CHANGE# TIME
---------- ---------- ---------------- ------------- -------------------
1 1 CURRENT 3228984 2013/11/06:00:14:08 可以看到RESETLOGS后的REDO日志的序号是1
2 0 UNUSED 0
3 0 UNUSED 0
SYS@bys1>conn test/test
Connected.
TEST@bys1>set time on
00:16:34 TEST@bys1>select * from cat;
TABLE_NAME TABLE_TYPE
TEST1 SYNONYM
00:16:39 TEST@bys1>conn / as sysdba
Connected.
00:16:45 SYS@bys1> select dbms_flashback.get_system_change_number from dual;
GET_SYSTEM_CHANGE_NUMBER
------------------------
3229504
00:16:57 SYS@bys1>drop user test cascade;
User dropped.
00:17:12 SYS@bys1>conn test/test
ERROR:
ORA-01017: invalid username/password; logon denied
Warning: You are no longer connected to ORACLE.
00:17:17 @bys1>conn / as sysdba
Connected.
00:17:21 SYS@bys1>shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
00:17:40 SYS@bys1>startup mount;
ORACLE instance started.
Total System Global Area 631914496 bytes
Fixed Size 1338364 bytes
Variable Size 385876996 bytes
Database Buffers 239075328 bytes
Redo Buffers 5623808 bytes
Database mounted.
############################################################
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