Oracle Backup and Recover 101. Osborne Press ISBN

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1 Oracle Backup and Recover 101 Osborne Press ISBN First Printing Personal Note from the Authors Thanks for your purchase of our book Oracle Backup & Recovery 101. In our attempt to provide the best book we could to guide you to a solid understanding of backup and recovery concepts and instructions, we painstakingly edited each chapter several times at many stages of development. Unfortunately, despite our efforts and those of the publisher, several errors made it into print. With each printing, we will identify any errors and post them in this document. If you find an error found in your copy that have not been listed in this document, please us at OracleBackupRecovery@yahoo.com. We appreciate your input. The authors, Kenny Smith & Stephan Haisley Errata Listing In this document, we identify content errors that you may have in your copy of the book. Formatting, minor typographical and presentation errors are not included in this errata listing. In many cases in this listing we are including the entire sentence, displaying the

2 current text that may be found in your book. We use a strike through font to show the words we d like to replace. We use a red color to denote the words we like to add. If a paragraph is has major changes, we show the paragraph before and the revised paragraph in full.this will make it easier for you to see how we intended the text to read in the book. Introduction Page xix - paragraph 5 By configuring database archiving of all redo log files, you can recover the database completely or to a point in time. Page xx - paragraph 1 Lastly, you ll incompletely recover the database while using an open database backup. Page xx - paragraph 6 All database transactions are logged to files. You can mine those files for the SQL commands contained within them. Page xxi - paragraph 1 LogMiner provides the means to extract the SQL commands within your log files. You can retrieve the transactional statements from the redo log files, which can then be reapplied to a database. During this chapter, you will analyze the contents of redo logs. Using the transactions statements retrieved, you ll be able to explore how to make use of the SQL by applying it to the database. Page xxi - paragraph 2 These seven chapters will also assist an old time DBA to migrate to a new skill set from the old tried-and-true user managed techniques. Most of the tasks discussed in Part Two can be accomplished quickly and easily by RMAN. Therefore, you can easily

3 contrast how you perform a specific task via user-managed method with the equivalent server-managed method. Chapter 1 Page 7 - paragraph 6 This way, the picture looks as it did before Sid accessed changed the picture frame. Page 12 - paragraph 7 (This paragraph belongs outside the gray box). After being introduced to Sid s family house, you can see that he has structures for all family procedures. Like this family operation, an Oracle database has places, processes, and procedures. With this family analogy in mind, I ll now briefly describe Oracle database structures, processes, and operations that pertain to Oracle Backup and Recovery. Maybe you ll recognize some similarities to Sid s family. Page 13 - paragraph 3 This area of memory that is allocated when the instance is started and is split up into three main sections: Page 15 - paragraph 1 It represents a consistent committed version of the database Page 17 - paragraph 4 They are called online because they must be online and available for the database to use.

4 Page 18 - paragraph 2 Change the note to Nologging and Redo You can turn off the logging of data block changes for certain operations by setting the NOLOGGING attribute for a table, partition, index, or tablespace. Normal SQL will create redo on a NOLOGGING object. Operations that will not create normal redo for changes include: - Direct load using SQL*Loader - Direct-load INSERT - CREATE TABLE... AS SELECT - CREATE INDEX - ALTER TABLE... MOVE or SPLIT PARTITION - ALTER INDEX... SPLIT or REBUILD PARTITION - ALTER INDEX... REBUILD These operations still generate redo records, but they are classed as 'invalidation records' and are very small compared to standard data block redo records. Because redo is not being generated from these data changes, the blocks affected must be invalidated should redo be applied to them. This means that once a NOLOGGING operation has been performed on objects, particularly tables, a fresh backup must be made of the datafiles containing them. If this is not done and an old backup is restored with the invalidation redo records being applied to the database, the next time you try and access the object you will get block corruption errors. When you prevent normal redo from being written, you trade better performance for data recoverability. Page Bullets Change the order of these bullets and add some text. Creates operation codes and data required to undo the block change into an undo segment (rollback segment). This also creates redo vectors before making the undo segment block changes. Records the redo records to the redo log buffer.

5 Page 25 Gray box Replace the gray box with this text. (s)the Life of a Database Transaction A user named Jim changes his home phone in the Employee Application from to He makes his change via a form in a browser. What happens to his phone number information? Say the employee table has a column named phone and the employee table is in a tablespace named Users. The Users tablespace is made up of a file named user.dbf. When Jim submits his change, the block containing his employee row is fetched from datafile user.dbf and read into the buffer cache. Before the changed phone number is placed in the data block in memory, a redo record gets written to log buffer. The redo record notes the block change from the old state to the new state. Next, undo information gets written to a rollback segment named RBS (in case Jim changes his mind and so other users can see his old phone number until he commits his change). After the redo and the undo is created, the data block containing Jim's row is changed. When Jim commits his change, a commit record is written to the log buffer. The log buffer is then flushed to the current online redo log. The undo blocks in the rollback segment are also freed. While Jim clicks on his sports web page to check the scores, the online redo log fills up. The database begins writing to the next empty redo log. If the data block containing Jim's phone number change has not been written out to disk due to lack of space in the buffer cache it will be written out during the checkpoint. The archiver begins to copy the online redo log containing Jim s transaction details. Once the archiver is finished, Jim s new phone number exists in two locations a database block in a file called user.dbf and in an archive log file in the archive destination. Page 27 Bottom bullets CKPT updates the control files and datafile headers with checkpoint details. The checkpoint gets logged in the alert log file.

6 Page 28 paragraph 1 When the database is shut down, various tasks occur depending on the shutdown method: Page 29 paragraph 1 Log switch Logan switches notebooks to hold picture negatives. An Oracle database stops writing to an online redo log file and begins writing to another. Chapter 2 Page 40 paragraph 2 This must be done because after an incomplete recovery, you do not need any of the redo after this time. Page 41 paragraph 1 production database or the tablespaces Page 46 paragraph 6 possibly use extra recovery Page 52 Question 4 The correct answer is only D. The A should be removed. Chapter 3 Page 55 Paragraph 5 During this chapter, you will install Oracle software, create two databases,. Page 60 Task 2 This Java program is named the Oracle Universal Installer. 1. Install Oracle Enterprise Version Your software version option may have different numbers in the last two digits, but make sure the first three digits are

7 2. For a Linux install, enter /app/oracle/product/8.1.7 in the Path field for the ORACLE_HOME directory. 3. For a Windows NT in the Oracle Home Name field, type 817. In the Path field, type D:\app\oracle\product\ Oracle on Windows NT has named Oracle Homes; Linux does not. Page 64 Task 1 LINUX> $ORACLE_HOME/bin/dbassist & WINNT> %ORACLE_HOME%\bin\launch.exe %ORACLE_HOME%\assistants\dbca DBAssist.cl Page 67 Exercise 3.3 The amount of total time is 55. (Not 50) Page 77 Middle of page SQL> execute DBMS_JOB.INTERVAL (1,null,null,'sysdate+1'); --Every day SQL> execute DBMS_JOB.INTERVAL (1,null,null,'sysdate+1/24'); --Every Hour SQL> execute DBMS_JOB.INTERVAL (1,null,null,'sysdate+1/(24*60)'); --Every Minute Chapter 4 Page 86 Figure 4-1 Backups in this chapter exercises will be written to /oradata/practice/backup/ch04. Page 88 Exercise 4.1: Task 1 Change the SQL statement from the tina.date_log table: SELECT TO_DATE TO_CHAR(max(create_date),...) Page 89 Closed Backup script Change line 18 of the script (add the ampersand): 18. &fil

8 Page 103 Exercise 4.4: Task 1 Change the SQL statement from the tina.date_log table: SELECT TO_DATE TO_CHAR(max(create_date),...) Page 107 paragraph 1 For cancel-based recovery in this exercise, you have to manually apply the log file names and then type CANCEL when you reach the log file that was current at the time of the tablespace drop. (Remove the apostrophe after CANCEL). Chapter 5 Throughout the chapter, change all references from directory /oradata/practice/backup/ch5 to /oradata/practice/backup/ch05. Page Figure 5-1 Change Tools0.1 to tools01. Change user.01 to users01. All exercises in this chapter create backups in the /oradata/practice/backup/ch05 directory. Page Second Bullet All subsequent changes to the same block create normal redo change vectors while the block still remains in the buffer cache. Page 119 Open Backup Script Change the line of the script that creates a backup of the control file to: prompt alter database backup controlfile to '&dir./control.ctl' REUSE;; Page Paragraph 2 The recover command determined that the redo needed for the recovery begins in archive file sequence from 221 to 51.

9 Page Task Table 5. Recover database to a point in time Page Last Code listing SQL> INSERT INTO tina.date_log VALUES (sysdate+(365*5)); SQL> COMMIT; Page Last Task heading Recover Database to Point in Time Page paragraph 4 Start Cancel-based recovery. Page paragraph 2 During database startup and shutdown, you may have some problems. Page paragraph 6 During database shutdown startup, you may get an error. Page answer 5 5. C. When you issue the ALTER TABLESPACE TOOLS BEGIN BACKUP command, the TOOLS tablespace undergoes a checkpoint. All changes for the files in that tablespace get recorded as block images to the redo files. Page gray box 2. The user running this command must be granted the OSDBA SYSDBA role. Page paragraph 4 This file will be located in the location directory defined by the user_dump_dest initialization parameter.

10 Page last paragraph On a startup NOMOUNT, you only read the init.ora file and establish the memory structures and background processes required by Oracle. Page first paragraph Both the online redo logs and the archived redo logs from the original database can no longer be used for this database once you reset the logs to include your new database name. Page Gray box - last sentence For extra credit, vary the file names, directories, and order. Note that once you get your database open, the file number from the v$datafile dictionary view is the same in the copied database as it is in original database. (I m not recommending you change the datafile order, but you can try this to help you understand the duplication process better.) Page First paragraph When you clone a database, you may (and probably will) run into various problems along the way. Usually, those problems show up in an error message during a task in the project. Page paragraph 2 The CLNE database may need redo in the current PRACTICE database archive online log. Chapter 6 Throughout the chapter, change all occurrences of the database and directory from STANDBY to STBY. Chapter 7 Page Task listing Remove task 3. The standby control file is made when the backup is taken.

11 Chapter 8 Page Bullet Full database mode The import parameter defining user database mode is FULL=Y. Page First paragraph Two parameters that create output and do not change the database are SHOW and INDEXFILE. Page Point 2 The text definitions in the log files have been wrapped within words double-quotes. Page paragraph 5 Create an export with three tables of Tina s table using a parameter file as shown in this example: Chapter 9 Page last bullet Any database files required for tablespace recovery. In this chapter, the auxiliary set is the primary PRACTICE database backup control file, backup datafiles of the SYSTEM, RBS and TEMP and RBS tablespaces, the auxiliary database parameter file and the primary PRACTICE database archived log files. Page first paragraph You will recover this table using TSPITR. Before you drop the table, first create rebuild an index on the employee table in the INDX tablespace. Page last paragraph Because any data changes made to objects in the USERS tablespace after TSPITR the drop table command will not be recovered, the support department will not be found in the department table.

12 Page Last paragraph By doing this, you avoid the risk of corrupting the primary database instance by writing over the control files, datafiles or online redo logs. Page first paragraph Then, you will recover the recovery set datafiles to prepare them for Export/Import transporting back into the PRACTICE database. Page first paragraph in Task 3 When you drop the tables tablespace including contents, the objects contained within it are removed from the data dictionary. Page Second Listing SQL> EXECUTE dbms_logmnr.add_logfile( - 2 logfilename => 'd:\oradata\practice\archive\100.arc', - 2 logfilename => '/oradata/practice/archive/100.arc', - 3 options => dbms_logmnr.removefile); Page First Paragraph You can see that someone logged in as user SCOTT and performed this update. You also know the culprit was logged on to a machine named SJCOMP as an operating system user named SJONES. Page LogMiner Once your investigation of the redo logs is completed, run the END_LOGMNR procedure of the DBMS_LOGMNR package. Page Summary Occasional analysis of the online redo log files can help you find out when table data is changed or perform capacity analysis on your Oracle database. LogMiner serves is a handy means to look at the contents of Oracle 8, 8i or 9i database redo logs.

13 Chapter 11 Page Figure 11-1 Remove the Channels line between the target database and Recovery Manager executable. Page Bullet Automated backup, restoration, and recovery RMAN reads the control file each time the database is backed up to make sure the correct structural contents (tablespaces, datafiles, control files, and archive log files) are backed up. Page Gray box After each backup, the second catalog also needs to be resynced to ensure that it contains the newly created backup information. Page Third bullet The alert log file on the target and the catalog database may contain helpful information for troubleshooting the MML. Chapter 12 Page First paragraph Second, let s talk about items that involve the destination of the backup set. Page First paragraph A full whole database backup will therefore include the current control file. Page Figure 12-1 The last Sunday Level 0 backup should be number 127 instead of 120. The same mistake is made in figure Page both Points named Finally Finally All the redo generated since the time of the Saturday backup will be applied.

14 Page First Paragraph In this task, you ll back up the database while it is open. The script in Listing 12-3 is the same as the script is in task 1 with one exception: the database is open instead of closed. This script demonstrates how easy this is. Page First Bullet including current controlfile in backupset The current control file is copied with the system tablespace datafile. This message line comes right after the system datafile copy backup. Page Second bullet Line 2 The database control files must be mounted to run any RMAN backup commands. Why? All database schema structural information is stored in the target control files. Page paragraph 4 These files must be protected to be absolutely sure that you can recover your database to a point in time in the past or to the current time. Page last paragraph When you run b_archive_delete.rcv, the DELETE INPUT qualifier instructs RMAN to delete the archive log files that have been backed up after they have been successfully Page question 1 What RMAN command creates a copy of used database file blocks? Chapter 13 Page paragraph 1 Throughout this chapter, you ll see many RMAN commands applied toward checking and maintaining cataloged backups of the PRACTICE database,

15 Page Last paragraph Not only can you perform a validation of a specific backup set, but you can also simulate a restore of the database or portions of a database using the Validate option on the RESTORE command. Finally, RMAN can validate that a recovery can be made to a previous point in time using an UNTIL parameter to set the desired stop point of recovery. Page 335 Thursday bullet Thursday Cumulative incremental level1 backup with tag THU_LEVEL1. Page Backup Archive Logs Open a SQL*Plus session as the catalog owner and run queries like you ve done in previous tasks (select from V$BACKUP_REDOLOG and RC_BACKUP_REDOLOG instead). Page Question 2 2. Which recovery catalog view shows backup sets made by RMAN? Chapter 14 No known errors. Chapter 15 Page First bullet For example, if you have the init.ora parameter CONTROL_FILE_RECORD_KEEP_TIME set to 21 days, you may not be able to restore from a backup taken two months ago. Page Figure 15-1 The arrows should not include exercise references.

16 Page paragraph 3 If, during all the output from the duplicate command script, you do not encounter an error script and you see the RMAN-06400: database opened message, the RMAN database duplication operation was a success! Page Last code listing SQL> CONNECT sys/practice@clne Page Paragraph 2 Create your backup duplicate database with the script shown in Listing Be sure to shut down the CLNE database and open the instance without mounting it prior to running this duplication script. Chapter 16 Page Dorecover Bullet DORECOVER Recovers the standby database using incremental datafile and archive log backups. Page Third Bullet You must have a backup, that includes a standby control file. Page Item 6 If tape backups are used, the standby server must have access to the Media Management Layer and tape library that the primary database uses to makes its backups. Page First bullet RMAN can store that special file in a datafile backup piece. This backup control file can also be used to restore the target database control file if needed. Page First paragraph This duplicate, however, is configured to be a STBY standby of the PRACTICE database.

17 Page Item 4 The backup containing the standby control file was performed within the current online redo log file. Redo information about the standby control file is contained in the current online redo log file. Make sure hat you ve switched log files so that RMAN can access redo information current when the standby control file was created. RMAN will read the archive log file. Page Table titles Change the word Duplication to Standby. Issue the duplicate database command while connect to the target, catalog and auxiliary. The standby control file is automatically by RMAN during standby creation. Chapter 17 Page Fifth Bullet Remove the bullet item. Check that data in other tablespaces contains data that was changed after the recovery time of the users tablespace. Page Server-Managed TSPITR column Performs automatic incomplete recovery and opens with RESETLOGS.