PL/SQL to add archived redo log files to logminer

Similar Questions

• A PL/SQL to add the archived redo log for logminer files - please help debug

  Hello
  
  I have a PL/SQL to add recovery logs a day archived files to logminer utility in order to catch all LMD, which happened for a paticular at a particular time scheme
  
  as below,
  
  -logmnr.sql
  
  Set serveroutput on
  
  declare
  
  v_redo_dictionary_file VARCHAR2 (100);
  v_archived_log_file VARCHAR2 (100);
  
  -catch all them archived redo logs today, put in a cursor
  
  CURSOR logfile_cur IS
  SELECT name from v$ archived_log WHERE the to_char (COMPLETION_TIME, 'dd_MM_yyyy') > '18_01_2010' and not in sequence # (select sequence # v$ archived_log WHERE DICTIONARY_BEGIN = 'YES' AND dictionary_end = 'YES');
  
  
  Start
  
  -Create the DICTIONARY file on the files of the SOURCE database redo
  
  sys. DBMS_LOGMNR_D.build (OPTIONS = > sys.) DBMS_LOGMNR_D.store_in_redo_logs);
  
  
  Select name from v_redo_dictionary_file from v$ archived_log where DICTIONARY_BEGIN = 'YES' AND dictionary_end = 'YES', and sequence # = (select MAX(sequence#) from v$ archived_log WHERE DICTIONARY_BEGIN = 'YES' AND dictionary_end = 'YES');
  
  -Add newspapers of dictionary files
  sys.dbms_logmnr.add_logfile (nom_fichier_journal = > v_redo_dictionary_file,)
  Options = > sys.dbms_logmnr.new);
  
  -Add the log files
  
  Open logfile_cur;
  
  LOOP
  
  SEEK logfile_cur INTO v_archived_log_file;
  EXIT WHEN logfile_cur % NOTFOUND;
  sys.dbms_logmnr.add_logfile (nom_fichier_journal = > v_archived_log_file);
  
  
  END LOOP;
  
  CLOSE Logfile_cur;
  
  -Start LogMiner, also enable the ddl
  
  sys.dbms_logmnr.START_LOGMNR (options = > dbms_logmnr.dict_from_redo_logs + dbms_logmnr.ddl_dict_tracking);
  
  EXCEPTION
  WHILE OTHERS
  THEN
  DBMS_OUTPUT. PUT_LINE (SQLERRM);
  
  END;
  /
  
  
  ###############
  SQL > @logmnr.sql
  ORA-01291: missing logfile
  
  PL/SQL procedure successfully completed.
  
  What I did wrong?
  
  Thank you very much
  Roy

  [Double wire | http://forums.oracle.com/forums/message.jspa?messageID=4035521#4035521]

• DB restore Archives not lost mode redo log file... restore from controlfile tr

  I have a 11g database I had taken an archive backup but has failed to take redo backup of log files...
  so, while I restored the PB... after formatting the machine... the oracle instance does not start.
  
  
  I create controlfile track but when I run it I get errors.
  given that I don't have the old log files... How can I get around this issue
  Thank you
  Here is the example of trace control file... Note that I can't create the redo log file
  given that the db will not climb up, it must be in mode nonmount
  and here's 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_. JOURNAL"
  SIZE 50 M 512 BLOCKSIZE,
  GROUP 2
  ' C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_2_80L7C375_. JOURNAL"
  SIZE 50 M BLOCKSIZE 512
  -STANDBY LOGFILE
  DATA FILE
  ' 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 do not have these 2 files... what should I do to work around this situation
  ' C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_1_80L7C259_. JOURNAL"
  SIZE 50 M 512 BLOCKSIZE,
  GROUP 2
  ' C:\ORACLEXE\APP\ORACLE\FLASH_RECOVERY_AREA\XE\ONLINELOG\O1_MF_2_80L7C375_. JOURNAL"
  SIZE 50 M BLOCKSIZE 512
  -STANDBY LOGFILE
  DATA FILE
  
  Published by: zycoz100 on February 27, 2013 22:57

  If you have a backup to cold (closing correctly database) without the redo logs, change this:

  CREATE CONTROLFILE REUSE DATABASE "XE" NORESETLOGS NOARCHIVELOG
  

  TO

  CREATE CONTROLFILE REUSE DATABASE "XE" RESETLOGS NOARCHIVELOG
  

  You need to change the NORESETLOGS RESETLOGS for Oracle to recreate online redo logs.

  Hemant K Collette

• What is the role of the archived in an incremental backup redo log files?

  I want to know, to which RMAN reads what block of data is changed after the last incremental backup.
  and what is the role of the archived in an incremental backup redo log files?
  
  Please guide.

  Hello

  First Querstion response->
  Each block of data in a data file contains a system change number (SCN), which is the SCN of the last change to the block. During an incremental backup, RMAN reads the RCS of each block of data in the input file and compares at the checkpoint SCN of the incremental backup from parent. If the RCS in the block of input data is greater than or equal to checkpoint SCN of the parent, then RMAN copies the block.

  2 - the archived redolog files are required for the restoration of the online of rman incremental backup in a consistent state.

  Thank you & best regards
  Rahul Sharma

• new with OMF online redo log files

  Hi all
  
  I'm using Oracle 11 g 2, I created my DB using Oracle managed (OMF) files.
  
  I wanted to re size my recovery connects so I went in an old redo logs fall and create a new.
  
  That was how my redo logs resembles. It was created by the creation of the DB with OMF format:

  .../app/oradata/ORCL11/onlinelog/o1_mf_1_6pfncw81_.log
  .../app/flash_recovery_area/ORCL11/onlinelog/o1_mf_1_6pfncx5z_.log
  .../app/oradata/ORCL11/onlinelog/o1_mf_2_6pfncxps_.log
  .../app/flash_recovery_area/ORCL11/onlinelog/o1_mf_2_6pfncz1v_.log
  .../app/oradata/ORCL11/onlinelog/o1_mf_3_6pfnczhd_.log
  .../app/flash_recovery_area/ORCL11/onlinelog/o1_mf_3_6pfnd0vw_.log

  using the script I created new below redo logs

  alter database add logfile group 1 (
  '.../app/oradata/ORCL11/onlinelog/redo1.log',  
  '.../app/flash_recovery_area/ORCL11/onlinelog/redo1.log') size 76m reuse;

  .........
  and I added the new redo log group
  

  alter database add logfile group 4 (
  '.../app/oradata/ORCL11/onlinelog/redo4.log',  
  '.../app/flash_recovery_area/ORCL11/onlinelog/redo4.log') size 76m reuse;

  I was not able to create the recovery logs, where is the name of the redo log file: o1_mf_1_6pfncw81_.log, since this is the format OMF.
  
  My question by creating my recovery connects the way does it have an impact? on the archiving of newspapers of recovery? any impact on the database for now, this isn't OMF?
  
  How can I create my redo logs with OMF format?
  
  Kind regards

  try: -.
  alter database add logfile Group 4;

  for example; -.

  SQL> alter database add logfile group 4;
  
  Database altered.
  
  SQL> select member from v$Logfile;
  
  MEMBER
  --------------------------------------------------------------------------------
  /home/u01/app/oracle/oradata/dbtest/redo03.log
  /home/u01/app/oracle/oradata/dbtest/redo02.log
  /home/u01/app/oracle/oradata/dbtest/redo01.log
  /home/u01/app/oracle/flash_recovery_area/DBTEST/onlinelog/o1_mf_4_75nmw33l_.log
  
  SQL> alter database add logfile group 5 size 100m;
  
  Database altered.
  
  SQL> select member from v$logfile;
  
  MEMBER
  --------------------------------------------------------------------------------
  /home/u01/app/oracle/oradata/dbtest/redo03.log
  /home/u01/app/oracle/oradata/dbtest/redo02.log
  /home/u01/app/oracle/oradata/dbtest/redo01.log
  /home/u01/app/oracle/flash_recovery_area/DBTEST/onlinelog/o1_mf_4_75nmw33l_.log
  /home/u01/app/oracle/flash_recovery_area/DBTEST/onlinelog/o1_mf_5_75nmyvjg_.log
  

  Published by: rajeysh on August 28, 2011 20:00

• That redo log files waiting?

  Hello Experts,

  I read articles on the log redo and undo segment files. I was wondering something very simple. That redo log files waiting in there? It stores the sql statements?

  Lets say that my update statement to modify 800 blocks of data. A unique single update statement can modify different data 800 right blocks? Yes, it may be true. I think that these data blocks can not hold buffers to the log to roll forward, right? I mean I know exactly what to do redo log buffer and redo log file. And I know that the task of backgrounding LGWR. But, I wonder if she she holds the data blocks? It is not supposed to hold data like cache buffer blocks, right?

  My second question is, rollback isn't effect to restore the newspaper to the right buffer? Because it does not need log buffer for effect do it again. Conversely, the restoration; statement is included in the restore log buffer by progression when someone isse, am I right?

  As far as I know, rollback interact directly with UNDO TABLESPACE?

  I hope that I have to express myself clearly.

  Thanks in advance.

  Here's my question:

  My second question is, rollback isn't effect to restore the newspaper to the right buffer? Because it does not need log buffer for effect do it again. Conversely, the restoration; statement is included in the restore log buffer by progression when someone isse, am I right?

  As far as I know, rollback interact directly with UNDO TABLESPACE?

  Yes, where else would the undo data come from? Undo tablespace contains the Undo segments that contain the Undo data required for the restoration of your transaction.

  I can say that rollback does not alter the data of the log buffer rede to the past. In other words, change vectors will be remain the same before restoration. Conversely, rollback command is also recorded in the log file of restoration by progression. As the name, all orders are saved in the REDO LOGS.

  I hope that I am wrong so far?

  Not sure why you even the buffer log roll forward for Rollback? This is the reason why I asked you it was for, where occurs the dose the cancellation? And the answer for this is that it happens in the buffer cache. Before you worry about the drivers of change, you must understand that it is not serious what contains where as long as there is no transaction recorded in the operating of the Undo segment table. If the operating table indicates that the transaction is longer there, there must be a cancellation of the transaction. Vectors of change are saved in the file log roll forward, while the restore happens on blocks of data stored in the file "data" undo blocks stored in the undo file "data".

  At the same time I read an article about redo and undo. In this article process transaction is explained. Here is the link http://pavandba.files.wordpress.com/2009/11/undo_redo1.pdf

  I found some interesting information in this article as follows.

  It is worth noting that during the restore process, recovery logs never participate. The only time where redo logs are read is retrieving and archiving. This is the concept of tuning key: redo logs are written on. Oracle does not read during normal processing. As long as you have sufficient devices so that when the ARC is reading a file, LGWR's writing to a different device, then there no contention for redo logs.

  If redo logs are never involved in the restoration process, how is it Oracle will then know the order of the transaction? As far as I know it is only written in redo logs.

  I have thoughts very amazed to Aman.

  Why you ask?

  Now, before giving a response, I say two things. One, I know Pavan and he is a regular contributor to this forum and on several other forums Facebook and two, with all due respect to him, a little advice for you, when you try to understand a concept, to stick to the Oracle documentation and do not read and merge articles/blog-posts from the web. Everone, which publishes on the web, has their own way to express things and many times, the context of the writing makes it more confusing things. Maybe we can erase the doubts that you can get after reading the various search results on the web.

  Redo logs used for the restoration, not to restore. The reason is the redo log files are applied in sequential order, and this is not the case when we look for the restoration. A restore is required to do for a few blocks away. Basically, what happens in a restoration, is that the records of cancellation required for a block of data are sought in the reverse order of their creation. The entry of the transaction is in the slot ITL of the block of data that point to the necessary undo bytes Address (UBA) using which oracle also knows what that undo the blocks would be necessary for the restoration of your transaction. As soon as the blocks of data will be cancelled, the ITL slots would be cleared as well.

  In addition, you must remember, until the transaction is not qualified as finished, using either a commit or a rollback, the cancellation of this data would remain intact. The reason for this is that oracle would ensure that undo data would be available to make the cancellation of the transaction. The reason why Undo data are also recorded in the journals of recovery is to ensure that in the event of the loss of the cancellation of the data file, retrieving them would be possible. Because it would also require changes that's happened on the blocks cancel, restore the vectors change associated with blocks of cancellation are also saved in the buffer log roll forward and, in the redo log files.

  HTH

  Aman...

• SIZE OF THE REDO LOG FILE

  
  Hello

  I got an error message when I add me new group. log files I searched and found the answer on the form. Ago 4 M minimum size of 11 g R2 log file size.

  My question is why a log file size depends on DB_BLOCK_SIZE? This parameter is set to the component structures of memory that create an instance when a log file is an operating system file that depend on the version of the OS not DB_BLOCK_SIZE.

  Thank you.

  
  SQL > alter database add logfile group 4 'c:\app\asif\oradata\employee\redo04.log' size 1 m;
  alter database add logfile group 4 'c:\app\asif\oradata\employee\redo04.log' size 1 m
  *
  ERROR on line 1:
  ORA-00336: 2048 blocks the size of the log file is minimum lower than 8192 blocks

  
  SQL > show parameter db_block_size

  VALUE OF TYPE NAME
  ------------------------------------ ----------- ------------------------------
  Whole DB_BLOCK_SIZE 8192
  SQL >

  You are assuming that the redo log block size is the same as the database block size. This is not correct.

  The error indicates that 8192 is the minimum number of blocks of a redo log file. The documentation states that the minimum size is 4 M. For example, you can deduct your redo log block size is 512 bytes.

  Here's some more information about the size of redo log, the documentation block.

  Unlike the database block size, which can always be between 2 K and 32 K, redo log default files to a block size that is equal to the size of physical sector of the disk. Historically, it is usually 512 bytes (512 b).

  Some new large disks offer 4K sizes byte (4K) to increase sector efficiency improved format and ECC capabilities. Most of the Oracle database platforms are able to detect this bigger sector size. The database then automatically creates files redo log with a block size of 4 K of these discs.

• Cannot add the new log file for the 11g database.

  Salvation of DBA
  
  I'm not able to add the log file, I receive the error message when the database is added.
  
  SQL > alter database add logfile group 3 ('/ oracle/DEV/db/apps_st/data/log03a.dbf','/oracle/DEV/db/apps_st/data/log03a.dbf') Re-use of size of 50 m;
  alter database add logfile group 3 ('/ oracle/DEV/db/apps_st/data/log03a.dbf','/oracle/DEV/db/apps_st/data/log03a.dbf') Re-use of 50 m of size
  *
  ERROR on line 1:
  ORA-01505: Error adding log files
  ORA-01577: cannot add the log file ' / oracle/DEV/db/apps_st/data/log03a.dbf'-fichier
  already a part of the database
  
  SQL > select a.group #, a.status, a member of the journal of v$ a, v$ logfile b where a.group # order of b.group = # 1;
  
  GROUP # MEMBER STATUS
  ---------- ---------------------------------------- ----------
  1 ACTIVE /oracle/DEV/db/apps_st/data/log01a.dbf
  1 ACTIVE /oracle/DEV/db/apps_st/data/log01b.dbf
  /Oracle/DEV/db/apps_st/data/log02a.dbf CURRENT 2
  /Oracle/DEV/db/apps_st/data/log02b.dbf CURRENT 2
  
  Kindly help me to add the new log file to my database.
  
  Thank you
  SG

  PGO

  Please see (how can redo log group be dropped when it ever becomes inactive?) [ID] 730827.1).

  Thank you
  Hussein

• How to find the configuration state of REDO logs files?

  I'm trying to move the redo log files.
  Before that, I want to know if it is set as a duplex or any other configuration.
  
  How to find the REDO log configurations.
  
  Oracle 10g R2
  
  Thank you
  Smith

  Example:

  Not in duplex redo log - if the number of members is 1, it is not duplex:

  SQL> select group#, members from v$log;
  
      GROUP#    MEMBERS
  ---------- ----------
           1          1
           2          1
           3          1
  
  SQL> select group#, member from v$logfile;
  
      GROUP# MEMBER
  ---------- --------------------------------------------------
           1 /u01/app/oracle/oradata/db1/redo01.log
           2 /u01/app/oracle/oradata/db1/redo02.log
           3 /u01/app/oracle/oradata/db1/redo03.log
  
  SQL> alter database add logfile member '/u01/app/oracle/oradata/db1/redo01_2.log' to group 1;
  
  Database altered.
  
  SQL> alter database add logfile member '/u01/app/oracle/oradata/db1/redo02_2.log' to group 2;
  
  Database altered.
  
  SQL> alter database add logfile member '/u01/app/oracle/oradata/db1/redo03_2.log' to group 3;
  
  Database altered.
  

  Duplex redolog

  SQL> select group#, members from v$log;
  
      GROUP#    MEMBERS
  ---------- ----------
           1          2
           2          2
           3          2
  
  SQL> select group#, member from v$logfile;
  
      GROUP# MEMBER
  ---------- --------------------------------------------------
           1 /u01/app/oracle/oradata/db1/redo01.log
           2 /u01/app/oracle/oradata/db1/redo02.log
           3 /u01/app/oracle/oradata/db1/redo03.log
           1 /u01/app/oracle/oradata/db1/redo01_2.log
           2 /u01/app/oracle/oradata/db1/redo02_2.log
           3 /u01/app/oracle/oradata/db1/redo03_2.log
  

• Questions about the parameters of database using a fast recovery area and the writing of two copies of archived redo logs.

  My databases are 11.2.0.3.7 Enterprise Edition. My OS is AIX 7.1.

  I am to convert databases to use individual zones of rapid recovery and have two questions about what values to assign to database settings related to archived redo logs. This example refers to a database.

  I read that if I specify

  Log_archive_dest_1 =' LOCATION = USE_DB_RECOVERY_FILE_DEST'

  the names of newspapers archived redo written in the default quick recovery area is '% t_%S_%r.dbf '.

  In the past my archived redo logs have been appointed based on the parameter

  log_archive_format='GPAIDT_archive_log_%t_%s_%r.arc'

  I think log_archive_format will be ignored for logs archived redo written in the fast recovery area.

  I am planning to write a second copy of the archived redo logs based on the parameter

  ALTER system set log_archive_dest_2 = ' LOCATION = / t07/admin/GPAIDT/arch.

  If I do this, the copy of logs placed in /t07 will be called '% t_%S_%r.dbf' or 'GPAIDT_archive_log_%t_%s_%r.arc '?

  Before my use of a fast recovery area, I used the OEM 12 c Console to specify settings of backup of database that has been deleted and archived redo logs after 1 backup. Oracle manuals say rather specify a deletion of "none" policy and allow Oracle delete newspapers in the area of fast recovery if necessary. Since I got to keep a second copy of these log files in /t07 should I keep the policy that says to delete logs after 1 backup? If I don't do that, how will they removed from /t07?

  Thank you

  Bill

  If I do this, the copy of logs placed in /t07 will be called '% t_%S_%r.dbf' or 'GPAIDT_archive_log_%t_%s_%r.arc '?

  They will be "GPAIDT_archive_log_%t_%s_%r.arc". LOG_ARCHIVE_FORMAT is only ignored for directories under OMF.

  Since I got to keep a second copy of these log files in /t07 should I keep the policy that says to delete logs after 1 backup? If I don't do that, how will they removed from /t07?

  You can hold the deletion policy as it is. Oracle documentation, defining the STRATEGY of the ARCHIVELOG DELETION: "the deletion of archived newspaper policy applies to logs archive destinations, including the area of fast recovery."

• Best location for the archived redo logs

  Hello

  I am OOF instructions and I want to make life for the DBA, that looks like my job easier.

  So, as the title says what is the location of the "standard/Best Practice' for archived redo logs? particularly the dest_1 which is usually local on the same server

  Thank you.

  Hello

  For you, I recommend the use of the Flash/fast recovery area.

  Configuration of the archived of Redo Log locations

  Oracle recommends that you use fast area recovery to an archive location, because the archived logs are managed automatically by the database. The file names generated for the newspapers archived in the fast recovery area correspond to Oracle managed files and are not determined by the parameter LOG_ARCHIVE_FORMAT . Whatever archiving scheme you choose, it is always advisable to create multiple copies of archived redo logs.

  Ref 1:

  http://docs.Oracle.com/CD/E11882_01/backup.112/e10642/rcmconfb.htm#CHDEHHDH

  Ref 2:

  http://docs.Oracle.com/CD/E11882_01/server.112/e17157/unplanned.htm#BABEEEFH

  REF 3:

  http://docs.Oracle.com/CD/E11882_01/backup.112/e10642/rcmconfb.htm#BRADV89418

  Kind regards

  Juan M

• I have to create the new group for waiting for redo log files?

  I have 10 group of files redo log with 2 members of each group for my primary database, I need to create new group for redo log files for the database of relief pending

  Group # members

  ==============

  1              2

  2              2

  3             2

  4             2

  5             2

  6             2

  7             2

  8             2

  9             2

  2 of 10

  If so, the following statement is correct? or nto

  ALTER DATABASE ADD STANDBY LOGFILE GROUP 1 ('D:\Databases\epprod\StandbyRedoLog\REDO01.) LOG',D:\Databases\epprod\StandbyRedoLog\REDO01_1.log');

  Please correct me if am doin wrong

  because when I run the statement I have error message saying: the group is already created.

  Thanks John

  I just found the answer

  Yes, it of recomeded to add the new group, for instnace if I have 10 group of 1 to 10, then the wait should be from 11 to 20

  Thanks I found the answer.

• bottleneck during the passage of the redo log files.

  Hi all
  
  I'm using Oracle 11.2.0.3.
  
  The enforcement team has indicated that they are facing slow at some point.
  
  I followed the database and I found that at some passage of redo log files (not always), I am facing a slow at the application level.
  
  I have 2 son since my database is CARS, each thread has 3 groups of multiplexed redo logs the FIU, with size of 300 MB each.
  
  Is it possible to optimize the switch of the redo log files? knowing that my database is running in ARCHIVELOG mode.
  
  Kind regards

  Hello

  Yes, Oracle recommends 1 validation by 30 calls from users or less. Of course, every database is different, so this rule cannot be taken too literally, but in your case, this rule seems to apply. In any case State, 900 undertakes seconds it looks like a very large number and the need for a high number of transactions should be questioned. You should talk to your analysts/application management/enterprise architect if warranted - that is to say if the application does in fact almost 2 000 business transactions per second.

  What about DB CPU: here is a link to a blog that I wrote on this subject, it should help to better understand this number:

  http://Savvinov.com/2012/04/06/AWR-reports-interpreting-CPU-usage/

  But briefly: DB processor isn't a real event, it is simply an indication that the sessions are on CPU (or waiting for CPU) rather than wait on i/o requests or events in the database. It is not necessarily a bad thing, because the database must perform tasks and he cannot do without loading the CPU. It may indicate a problem in two cases: when the CPU usage is close to the limit of the host (OS stats section indicates that you are very far from there) or when the CPU is a % of DB time - in the latter case, this could mean that you are making too many logical reads due to inefficient plans or analysis too. In any case, this does not apply to you, because 20 percent is not very high a number.

  Other items in the list of the top 5 deserve attention, too - gc buffer busy acquire, gc current block busy, enq: TX - line lock conflict.

  To summarize, your database under a lot of stress - whether it is the legitimate workload, and if this is the case, you may need to upgrade your hardware later. There is chance that it isn't - for example a high number of runs may indicate that rather than to bulk operations database code using PL/SQL loops, which is a big performance killer. Check "Top SQL by executions" about whether or not this is the case.

  Good luck!

  Best regards
  Nikolai

• Redo log entries to the online redo log files

  Hello

  I'm a little confused about the redo log entries.

  I learned that LGWR writes redo log entries in the SGA, in redo log files in the following situation:

  -3 seconds after the last validation

  -redo log buffer has 1 MB

  -redo log buffer data 1/3

  When I take a transaction and if I change the wrong data, I have to cancel this transaction BUT the right now,

  What happens if the LGWR writes redo log disk entries?

  Is the bad transaction committed at all times?

  2791011 wrote:

  Hello

  I'm a little confused about the redo log entries.

  I learned that LGWR writes redo log entries in the SGA, in redo log files in the following situation:

  -3 seconds after the last validation

  -redo log buffer has 1 MB

  -redo log buffer data 1/3

  When I take a transaction and if I change erroneous data, I have to cancel this transaction at this time, BUT

  What happens if the LGWR writes redo log disk entries?

  Is the bad transaction committed at all times?

  DML changes are "permanent" after that VALIDATION is issued.

  When any COMMIT is issued, then changes can be undone.

• What is the purpose of waiting for redo log files

  Hello
  
  What is the purpose of the log files waiting for redo in the Dr?
  
  What happens if the standby redo log files are created? or else is not created?
  
  Please explain
  
  Thank you

  Re: what is the difference between onlinelog and standbylog

  I mentioned the goal of the eve of the redo log in RD files in above thread.

  Concerning
  Girish Sharma