Redo log content in NOARCHIVELOG mode

I have several servers running Oracle 9i databases in NOARCHIVELOG mode. I know this means that the online redo logs are not archived. I have been tracing the Oracle log writer with truss, and only see I/O going to the Oracle control files. I see no I/O going to the online redo logs. Can someone point me to the Oracle documentation that discusses exactly what gets written to the online redo log files while in NOARCHIVELOG mode? Thanks in advance for any assistance.

Try Oracle Concepts on
http://download-uk.oracle.com/docs/cd/B10501_01/server.920/a96524.pdf

Similar Messages

Multiplexing Redo Log and maximum protection mode.

Assume that during writing into redo logs the instance crashes. As a result, members of active redo group are not synchronized, some of them had more data. How Oracle will handle this when instance starts? And there can be case when at startup time some members that had more redo before crash, are lost.
Now assume that we have standby database with maximum protection mode. After LGWR has written to local redo logs and before writing to standby redo logs, primary instance crashes. In this case standby site lost last transaction.
Is it correct? Thanks.

Assume that during writing into redo logs the instance crashes. As a result, members of active redo group are not synchronized, some of them had more data. How Oracle will handle this when instance starts? And there can be case when at startup time some members that had more redo before crash, are lost.
Members of a particular group are written concurrently by LGWR, all members of a log group will have same data. If any member of a particular group is lost or not reachable, oracle will read from the available log member during instance recovery.
Multiplexing Redo Log Files
http://docs.oracle.com/cd/B19306_01/server.102/b14231/onlineredo.htm#i1006249
To answer your second question,In this mode no transaction commits on primary unless the redo is also written on atleast one standby database, otherwise primary will go down.
Check below
Maximum Protection
http://docs.oracle.com/cd/B28359_01/server.111/b28294/protection.htm#CHDHFHJI

LOB-redo log content

Hi,
we have to take over an new applicaion in production.
We worry about the redo log volume, because we have much tables
whith LOB columns. So I want to know, which redo informations were
generated when an LOB will be inserted. I can't believe that the hole content
of the lob will be written to the redo log. I can't find a detailed description
in the manuals. Thanx for any explanation.

Hi
Oracle must write everything that change in the redo logs... otherwise how it will be possible to perform a recovery?
Only exception is, for some operations, when NOLOGGING is enabled. This "option" is usually set at table level, with LOBs you can set it at LOB level.
Chris

How to recover from one corrupted redo log file in NOARCHIVE mode?

Oracle 10.2.1.
The redo log file was corrupted and Oracle can't work.
When I use STARTUP mount, I got no error msg.
SQL> startup mount
ORACLE instance started.
Total System Global Area 1652555776 bytes
Fixed Size 1251680 bytes
Variable Size 301991584 bytes
Database Buffers 1342177280 bytes
Redo Buffers 7135232 bytes
Database mounted.
But I have some applications which are depended on Oracle can't be started.
So, I tried STARTUP open. But I got error msg.
SQL> startup open
ORACLE instance started.
Total System Global Area 1652555776 bytes
Fixed Size 1251680 bytes
Variable Size 301991584 bytes
Database Buffers 1342177280 bytes
Redo Buffers 7135232 bytes
Database mounted.
ORA-00368: checksum error in redo log block
ORA-00353: log corruption near block 497019 change 42069302 time 11/07/2007
23:43:09
ORA-00312: online log 4 thread 1:
'G:\ORACLE\PRODUCT\10.2.0\ORADATA\NMDATA\REDO04.LOG'
So, how can I restore and recover my database?
If use RMAN, how to do that?
Any help will be appreciated.
Thanks.

Hi, Yingkuan,
Thanks for the helps.
Actually, I have 10 redo log files exists. All of them are here.
I tried your suggestion:
alter database clear unarchived logfile group 4;
The error msg I got is the same as before:
SQL> alter database clear unarchived logfile group 4;
alter database clear unarchived logfile group 4
ERROR at line 1:
ORA-01624: log 4 needed for crash recovery of instance nmdata (thread 1)
ORA-00312: online log 4 thread 1:
'G:\ORACLE\PRODUCT\10.2.0\ORADATA\NMDATA\REDO04.LOG'
Compared to losing all the data, it is OK for me lose some of them.
I have more than 1 TB data stored and 99.9% of them are raster images.
The loading of these data were the headache. If I can save them, I can bear the lost.
I want to grasp the last straw.
But I don't know how set the parameter: allowresetlogs_corruption
I got the error msg:
SQL> set allowresetlogs_corruption=true;
SP2-0735: unknown SET option beginning "_allow_res..."
I have run the command:
Recover database until cancel
Alter database open resetlogs
The error msg I got is the following:
SQL> recover database until cancel
ORA-00279: change 41902930 generated at 11/05/2007 22:01:48 needed for thread 1
ORA-00289: suggestion :
D:\ORACLE\PRODUCT\10.2.0\FLASH_RECOVERY_AREA\NMDATA\ARCHIVELOG\2007_11_09\O1_MF_
1_1274_%U_.ARC
ORA-00280: change 41902930 for thread 1 is in sequence #1274
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
cancel
ORA-01547: warning: RECOVER succeeded but OPEN RESETLOGS would get error below
ORA-01194: file 1 needs more recovery to be consistent
ORA-01110: data file 1: 'D:\ORACLE\PRODUCT\10.2.0\ORADATA\NMDATA\SYSTEM01.DBF'
ORA-01112: media recovery not started
SQL>
From the log file, I got the following:
ALTER DATABASE RECOVER database until cancel
Fri Nov 09 00:12:48 2007
Media Recovery Start
parallel recovery started with 2 processes
ORA-279 signalled during: ALTER DATABASE RECOVER database until cancel ...
Fri Nov 09 00:13:20 2007
ALTER DATABASE RECOVER CANCEL
Fri Nov 09 00:13:21 2007
ORA-1547 signalled during: ALTER DATABASE RECOVER CANCEL ...
Fri Nov 09 00:13:21 2007
ALTER DATABASE RECOVER CANCEL
ORA-1112 signalled during: ALTER DATABASE RECOVER CANCEL ...
Thank you very much. and I am looking forward to your followup input.

Current redo log file is lost

Hi All,
I got a scenario in which my current redo log file is lost:
Do I need to:
1)Clear log file group
(or)
2)I should perform incomplete recovery.
What are the steps I should follow to recover this current redo log file?
1)*If it is inactive* I can make use of
ALTER DATABASE CLEAR LOGFILE UNARCHIVED GROUP 2;
which will drop and recreate the log file.To recover from loss of an active online log group in NOARCHIVELOG mode:
If the media failure is temporary, then correct the problem so that the database can reuse the group when required.
Restore the database from a consistent, whole database backup (datafiles and control files) as described in "Restoring Datafiles Before Performing Incomplete Recovery". For example, enter:
% cp /disk2/backup/*.dbf $ORACLE_HOME/oradata/trgt/
Mount the database:
STARTUP MOUNT
Because online redo logs are not backed up, you cannot restore them with the datafiles and control files. In order to allow the database to reset the online redo logs, you must first mimic incomplete recovery:
RECOVER DATABASE UNTIL CANCEL
CANCEL
Open the database using the RESETLOGS option:
ALTER DATABASE OPEN RESETLOGS;
Shut down the database consistently. For example, enter:
SHUTDOWN IMMEDIATE
Make a whole database backup.
To recover from loss of an active online redo log group in ARCHIVELOG mode:
If the media failure is temporary, then correct the problem so that the database can reuse the group when required. If the media failure is not temporary, then use the following procedure.
Begin incomplete media recovery, recovering up through the log before the damaged log.
Ensure that the current name of the lost redo log can be used for a newly created file. If not, then rename the members of the damaged online redo log group to a new location. For example, enter:
ALTER DATABASE RENAME FILE "?/oradata/trgt/redo01.log" TO "/tmp/redo01.log";
ALTER DATABASE RENAME FILE "?/oradata/trgt/redo01.log" TO "/tmp/redo02.log";
Open the database using the RESETLOGS option:
ALTER DATABASE OPEN RESETLOGS;
My question is when the redo log file is current. What steps we should follow?
Best regards,
Rafi.
http://rafioracledba.blogspot.com/
2)If it is active then I can make use of below steps:

Rafi (Oracle DBA) wrote:
Hi Asif,
This link I have seen by refering to previous post.I just have a slight doubt in mind.
1)Do I need to make use of statement:
Alter database clear unarchived log file group#;
(or)
Only if your group is current(or you are not able to drop it) and is not archived then you should use above query.
We should perform incomplete recovery for this.If we have to perform incomplete recovery what are the steps I should follow?
I doubt you should be performing incomplete recovery for this.
Eg:Let us say my group 1 is dropped it has only one member and it is in active state.How to recover database?Can I get the steps?
You would not be able to drop it if it is in active state, did you meant it is corrupted? If yes then you can use below query
Alter database clear [unarchived] LOGFILE GROUP #;>
Best regards,
Rafi
http://rafioracledba.blogspot.com/
Make sure to backup your database after above activity.
Regards
Anurag

Online Redo logs instead of Standby Redo logs

RDBMS Version: 11.2.0.3/Platform : RHEL 6.3
To migrate a 3TB Database to a new DB server , we are going to use RMAN DUPLICATE.
Step1. Take full backup of DB + Standby Control file at primary site and transfer the Bkp files to Standby site
Step2. At standy site, we will run the RMAN duplicate target database for standby
After the above step, we don't want to create the standby redo logs because the newly restored DB in standby server is going to be the new Prod DB which application will be pointing to.
So, Can I skip the Standby Redo log creation part and create Online redo logs instead ?
As mentioned earlier, Our objective is not to create a proper Dataguard Standby DB setup. We just want to clone our DB to another server using RMAN Duplicate.

Tom wrote:
RDBMS Version: 11.2.0.3/Platform : RHEL 6.3
To migrate a 3TB Database to a new DB server , we are going to use RMAN DUPLICATE.
Step1. Take full backup of DB + Standby Control file at primary site and transfer the Bkp files to Standby site
Step2. At standy site, we will run the RMAN duplicate target database for standby
After the above step, we don't want to create the standby redo logs because the newly restored DB in standby server is going to be the new Prod DB which application will be pointing to.
So, Can I skip the Standby Redo log creation part and create Online redo logs instead ?
As mentioned earlier, Our objective is not to create a proper Dataguard Standby DB setup. We just want to clone our DB to another server using RMAN Duplicate.
Hi,
Take full backup of DB + Standby Control
We just want to clone our DB to another server using RMAN Duplicate
If you want only clone database of production, why you are take Standby controlfile?
If you don't want create standby database then, why you using DUPLICATE command with FOR STANDBY option.
You can use DUPLICATE command for clone database, without for standby option.
If you say no, we want create standby database and we will perform swithover,
then yes, you can use online redo logs for max performance mode.
and you can create standby redo logs on all database, but this redo logs will use by database when database role
is standby.
Regards
Mahir M. Quluzade

Redo log entries

what do you mean by change vectors? what exactly do they contain?

Thank you for your replay.
checked out the link suggested and found the following content.
Online Redo Log Contents
Online redo log files are filled with redo records. A redo record, also called a redo entry, is made up of a group of change vectors, each of which is a description of a change made to a single block in the database. For example, if you change a salary value in an employee table, you generate a redo record containing change vectors that describe changes to the data segment block for the table, the rollback segment data block, and the transaction table of the rollback segments.
Redo entries record data that you can use to reconstruct all changes made to the database, including the rollback segments.
but still i am not clear with this concept
does it contain address of blocks in data & undo segments or the unit by which the data is changing?

Redo log files in case of NOARCHIVELOG Mode.

Question is related with the oracle architure..
database requires a minimum of two redo log files to guarantee that one is always available for writing while the other is being archived, this sounds perfect when DB is running in ARCHIVELOG mode but at the same time it also forces database to have 2 redo log files even when the DB is running in NOARCHIVELOG mode?
Any particular reason..
I would look for reasons not answers on what redo log is and what information it holds etc..

pgoel wrote:
If you had only one file all further changes would have to stop until all changed data blocks had been written to disc. By insisting on a minimum of two log files Oracle can allow the log writer to fill the second log file as the database writer writes out the dirty blocks covered by changes desrcibed in the first log file.What about having a big size redo log file instead of two? Checkppoint being initiated when the redo log file is half filled
I mean, understand the logic, two is better, even best.. but still not getting convinced. I am just trying to think, can not Oracle work with 1 group with 1 big file..specailly when Noarch mode ? Having
Edited by: pgoel on Mar 12, 2011 7:27 PMNo, you still didn't understand and I am not sure how else we can say it. Okay, think about log groups as two buckets which are used to fill the redo content. The LGWR is filling one bucket at a time till it can't accept any more content. Once filled, rather than spilling the content out, it jumps over to the second bucket. Now, taking your statement of big sized redo, Pgoel, it doesn't matter how big sized bucket you bring in, eventually it will fill in. Its not possible that you wont be able to fill it , it just would take more longer than the normal timings. Thats all. So in any case , you need the second bucket. And I am not sure that why you are struck on the archivelog mode. I hope you do understand that its an optional mode. This means, this may or may not be there. If there, its a good thing that before doing the flush of the redo content, Oracle would be able to save the contents in the archived (think about the name, it's very meaning is to preserve, to archive) log file. If not, the redo content wuold be lost and there won't be any record of transactions leaving you to reenter the lost transactions. Its a meaningless point on which you are struck i.e. the archive or no-archivelog mode. Be it whatever, Oracle would still need minimum of the two log groups.
HTH
Aman....

Restore in noarchivelog mode ( redo log files have been dropped )

1, A full backup taken using RMAN is available on disk.
2, The current control files were NOT damaged and do not need to be restored.
3, All data files are damaged .
4, The database is in NOARCHIVELOG mode.
I restore database :
1. RMAN> STARTUP MOUNT
2. RMAN> RESTORE DATABASE;
3. RMAN> recover database;
in this step , I got the information about needing redo log files ; but the redo log
files have been dropped , what should i do ?
else
I want to know there is the command 'recover database using backup control file'
in rman or not ?
Tks

Possibly loss of data (because information in online redo logs is lost):
recover database until cancel;
(cancel immediately)
alter database open resetlogs; (to build a new set of redo logs)
It's not necessary to use a backup controlfile here.

Redo log in case of NOARCHIVELOG Mode.

================================================
This post is now available at .. Redo log files in case of NOARCHIVELOG Mode.
================================================
Question is related with the oracle architure..
database requires a minimum of two redo log files to guarantee that one is always available for writing while the other is being archived, this sounds perfect when DB is running in ARCHIVELOG mode but at the same time it also forces database to have 2 redo log files even when the DB is running in NOARCHIVELOG mode?
Any particular reason..
I would look for reasons not answers on what redo log is and what information it holds etc..
Edited by: pgoel on Mar 12, 2011 4:04 PM

======================================
SORRY, WRONG FORUM moving it to the corrent forum
======================================
Edited by: pgoel on Mar 12, 2011 4:01 PM

ORA-00258: manual archiving in NOARCHIVELOG mode must identify log

Hi I am new to oracle streams. I am trying to setup a one way replication from one database to another using Oracle 10g (10.2.0.1.0) on Windows XP SP3 (32 bit).
I ran the following proc as the streams admin schema:
begin
dbms_streams_adm.maintain_schemas(
schema_names => 'XXCOW',
source_directory_object => 'repl_exp_dir',
destination_directory_object => 'repl_imp_dir',
source_database => 'PWBSD',
destination_database => 'PDVSD',
perform_actions => true,
dump_file_name => 'exp_app23.dmp',
capture_queue_table => 'rep_capt_table',
capture_queue_name => 'rep_capt_queue',
capture_queue_user => NULL,
apply_queue_table => 'rep_dest_table',
apply_queue_name => 'rep_dest_queue',
apply_queue_user => NULL,
capture_name => 'capture_pubs',
propagation_name => 'prop_pubs',
apply_name => 'apply_pubs',
log_file => 'exp_app23.log',
bi_directional => false,
include_ddl => true,
instantiation => dbms_streams_adm.instantiation_schema);
end;
The script failed the first time because i forgot to configure the source database in archive log mode.
The steps i followed to change to archivelog mode:
SQL> select name from v$database;
NAME
PWBSD
SQL> alter system set LOG_ARCHIVE_DEST = 'D:\data\oracle\oradata\PWBSD\archive' scope=both;
System altered.
SQL> conn sys/sys@pwbsd as sysdba
Connected.
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount
ORACLE instance started.
Total System Global Area 612368384 bytes
Fixed Size 1250428 bytes
Variable Size 197135236 bytes
Database Buffers 406847488 bytes
Redo Buffers 7135232 bytes
Database mounted.
SQL> alter database archivelog;
Database altered.
SQL> alter database open;
Database altered.
SQL>
I configured it in archive log mode and ran the proc above again.
I got the following output this time:
job finished
begin
ERROR at line 1:
ORA-23616: Failure in executing block 90 for script
959ECF1D1159402A8C16687AE5E3B5CD
ORA-06512: at "SYS.DBMS_RECOVERABLE_SCRIPT", line 457
ORA-06512: at "SYS.DBMS_STREAMS_MT", line 2201
ORA-06512: at "SYS.DBMS_STREAMS_MT", line 7486
ORA-06512: at "SYS.DBMS_STREAMS_ADM", line 2624
ORA-06512: at "SYS.DBMS_STREAMS_ADM", line 2685
ORA-06512: at line 2
I ran the following to check the error:
select * from dba_recoverable_script_errors;
The output is:
SCRIPT ID: 959ECF1D1159402A8C16687AE5E3B5CD
BLOCK NUM: 90
ERROR_NUMBER: -258
ERROR_MESSAGE: ORA-00258: manual archiving in NOARCHIVELOG mode must identify log
ORA-06512: at "SYS.DBMS_RECO_SCRIPT_INVOK", line 129
ORA-06512: at "SYS.DBMS_STREAMS_RPC", line 358
It seemed like it was still complaining about archive log mode,
I verified that the PWBSD db is in archivelog mode by running the following:
select name, log_mode from v$database;
NAME: PWBSD
LOG_MODE: ARCHIVELOG
What could be the problem and how do i proceed to fix it?

Hi Parthiv,
The steps given by you is not clear.
please try to fallow the steps given in the below link. It may be helpful to you to setup schema level streams:
http://gssdba.wordpress.com/2011/04/20/steps-to-implement-schema-level-oracle-streams/
Thanks and Regards,
Satish.G.S
gssdba.wordpress.com

Can we use online redo log to recover lost datafile in NOARCHIVE mode?

I am working on OCA exam and confued about these 2 sample questions. (similar questions with totally different answer)
Please give me hint about the different between these 2 questions.
** If the database is in NOARCHIVELOG mode, and one of the datafile for tablespace USERS is lost, what kind of recovery is possible? (answer: B)
A. All transactions except those in the USERS tablespace are recoverable up to the loss of the datafile.
B. Recovery is possible only up to the point in time of the last full database backup.
C. The USERS tablespace is recoverable from the online redo log file as long as none of the redo log files have been reused since the last backup.
D. Tablespace point in time recovery is available as long as a full backup of the USERS tablespace exists.
** The database of your company is running in the NOARCHIVELOG mode. You perform a complete backup of the database every night. On Monday morning, you lose the USER1.dbf file belonging to the USERS tablespace. Your database has four redo log groups, and there have been two log switches since Sunday night's backup.
Which is true (answer: B)
A. The database cannot be recovered.
B. The database can be recovered up to the last commit.
C. The database can be recovered only up to the last completed backup.
D. The database can be recovered by performing an incomplete recovery.
E. The database can be recovered by restoring only the USER!.dbf datafile from the most recent backup.

I think Gaurav is correct, you can recover to the last commit even in NOARCHIVELOG, as long as all the changes in the redo logs have not been overwritten. So answer should be B for question 2.
Here is my test:
SQL> select log_mode from v$database;
LOG_MODE
NOARCHIVELOG
SQL> select tablespace_name, file_name from dba_data_files;
TABLESPACE_NAME
FILE_NAME
USERS
C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\USERS01.DBF
SYSAUX
C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\SYSAUX01.DBF
UNDOTBS1
C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\UNDOTBS01.DBF
SYSTEM
C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\SYSTEM01.DBF
DATA
C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\DATA01.DBF
SQL> create table names
2 ( name varchar(16))
3 tablespace users;
Table created.
so this segment 'names' is created in the datafile users01.
At this point I shut down and mount the DB, then:
RMAN> backup database;
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:29
Finished backup at 06-OCT-07
SQL>alter database open
SQL> insert into names values ('pippo');
1 row created.
SQL> commit;
Commit complete.
SQL>shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
At this point I delete datafile users01 and restart:
SQL> startup
ORACLE instance started.
Total System Global Area 167772160 bytes
Fixed Size 1247900 bytes
Variable Size 67110244 bytes
Database Buffers 96468992 bytes
Redo Buffers 2945024 bytes
Database mounted.
ORA-01157: cannot identify/lock data file 4 - see DBWR trace file
ORA-01110: data file 4: 'C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\USERS01.DBF'
restoring the backup taken before inserting the value 'pippo' in table names:
RMAN> restore database;
Starting restore at 06-OCT-07
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile backupset restore
channel ORA_DISK_1: specifying datafile(s) to restore from backup set
restoring datafile 00001 to C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\SYSTEM01.D
BF
restoring datafile 00002 to C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\UNDOTBS01.
DBF
restoring datafile 00003 to C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\SYSAUX01.D
BF
restoring datafile 00004 to C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\USERS01.DB
F
restoring datafile 00005 to C:\ORACLE\PRODUCT\10.2.0\ORADATA\ORA101RC\DATA01.DBF
channel ORA_DISK_1: reading from backup piece C:\ORACLE\PRODUCT\10.2.0\DB_1\DATA
BASE\0AITR52K_1_1
channel ORA_DISK_1: restored backup piece 1
piece handle=C:\ORACLE\PRODUCT\10.2.0\DB_1\DATABASE\0AITR52K_1_1 tag=TAG20071006
T181337
channel ORA_DISK_1: restore complete, elapsed time: 00:02:07
Finished restore at 06-OCT-07
RMAN> recover database;
Starting recover at 06-OCT-07
using channel ORA_DISK_1
starting media recovery
media recovery complete, elapsed time: 00:00:05
Finished recover at 06-OCT-07
SQL> alter database open;
Database altered.
SQL> select * from names;
NAME
pippo
SQL>
enrico

Db restore non archive mode lost redo log file..restore from controlfile tr

i have a db 11g I had taken non archive backup but failed to take redo log files backup...
so while i restored the db ... after formatting the machine ..the oracle instance wont start.
I create a controlfile trace but when i run it i get errors.
since i dont have the older log files.. how do i get around with this issue
Thanks
Following is the sample of control file trace ..Note i cannot create the redo log file
since db wont be mounted at most it shall be in nonmount mode
and below is my created controlfile ....
CREATE CONTROLFILE REUSE DATABASE "XE" NORESETLOGS NOARCHIVELOG
MAXLOGFILES 16
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 8
MAXLOGHISTORY 292
LOGFILE
GROUP 1
'C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_1_80L7C259_.LOG'
SIZE 50M BLOCKSIZE 512,
GROUP 2
'C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_2_80L7C375_.LOG'
SIZE 50M BLOCKSIZE 512
-- STANDBY LOGFILE
DATAFILE
'C:\ORACLEXE\APP\ORACLE\ORADATA\XE\SYSTEM.DBF',
'C:\ORACLEXE\APP\ORACLE\ORADATA\XE\UNDOTBS1.DBF',
'C:\ORACLEXE\APP\ORACLE\ORADATA\XE\SYSAUX.DBF',
'C:\ORACLEXE\APP\ORACLE\ORADATA\XE\USERS.DBF'
CHARACTER SET AL32UTF8
I dont have these 2 files ..what do i do to get around this situation
'C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_1_80L7C259_.LOG'
SIZE 50M BLOCKSIZE 512,
GROUP 2
'C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_2_80L7C375_.LOG'
SIZE 50M BLOCKSIZE 512
-- STANDBY LOGFILE
DATAFILE
Edited by: zycoz100 on Feb 27, 2013 10:57 PM

If you have a cold backup (database shutdown properly) without the redo logs, change this :
CREATE CONTROLFILE REUSE DATABASE "XE" NORESETLOGS NOARCHIVELOGto
CREATE CONTROLFILE REUSE DATABASE "XE" RESETLOGS NOARCHIVELOGYou have to change the NORESETLOGS to RESETLOGS for Oracle to recreate the online redo logs.
Hemant K Chitale

Need to understand when redo log files content is wrote to datafiles

Hi all
I have a question about the time when redo log files are wrote to the datafiles
supposing that the database is in NOARCHIVELOG mode, and all redo log files are filled, the official oracle database documentation says that: *a filled redo log file is available
after the changes recorded in it have been written to the datafiles* witch mean that we just need to have all the redo log files filled to "*commit*" changes to the database
Thanks for help
Edited by: rachid on Sep 26, 2012 5:05 PM

rachid wrote:
the official oracle database documentation says that: a filled redo log file is available after the changes recorded in it have been written to the datafiles It helps if you include a URL to the page where you found this quote (if you were using the online html manuals).
The wording is poor and should be modified to something like:
<blockquote>
+"a filled online redo log file is available for re-use after all the data blocks that have been changed by change vectors recorded in the log file have been written to the data files"+
</blockquote>
Remember if a data block that is NOT an undo block has been changed by a transaction, then an UNDO block has been changed at the same time, and both change vectors will be in the redo log file. The redo log file cannot, therefore, be re-used until the data block and the associated UNDO block have been written to disc. The change to the data block can thus be rolled back (uncommitted changes can be written to data files) because the UNDO is also available on disc if needed.
If you find the manuals too fragmented to follow you may find that my book, Oracle Core, offers a narrative description that is easier to comprehend.
Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
Author: <b><em>Oracle Core</em></b>

Database in log archive mode and redo log file in mode not archive

Hello,
I have a dabatabase running in archive log mode, recently changed, I have 5 redo log groups and one of them (the current one) shows in the v$log view, that ARC: NO, I mean, no archiving. All redo logs except it shows ARC:Yes
What does it mean?
Am I going to have problems with this redo log file?
Thanks

If you do describe on v$log, you'll find that the full column name is Archived (meaning is it archived yet?).
You could try alter system switch logfile and then check v$log again a few times after.
Use the docu for finding out more about v$ views and so on
http://www.oracle.com/pls/db102/print_hit_summary?search_string=v%24log

Redo log content in NOARCHIVELOG mode

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