Oracle Backup Recovery Interview Questions during Technical discussion - A sample chapter:
Here are some interview questions and answers on Oracle Backup and Recovery. All of these interview questions and answers in real-time Oracle DBA interview questions and answers. Be careful with Oracle DBA interviews, as well as very strange SQL issues can be discussed during the interview. As a Oracle DBA candidate you can't eliminate the real time scenario based backup and recovery interview questions during Oracle DBA interviews.
Some strange interview questions are really very simple, but we found strange because you are not familiar with these types of questions and answers. Most of cases candidate failed due to not preparing proper interview questions and answers.
After all Oracle DBA interview questions and answers are sampling our outstanding book "Oracle DBA interview questions and answers". These questions are only examples from chapter of primary book. Total more than 80 questions and answers are covering in our "Oracle DBA Interview Questions And Answers" book.
A sample chapter of the book Oracle DBA Interview Questions - topics discussed in this chapter test "Oracle Backup and Recovery without RMAN".
Oracle versions are constantly being update with the enhancements in the current technology. It is thus very important for the database administrators to keep pace with this trend otherwise they may be rendered obsolete in the market. It is due to this kind of changes in technology that one is required to attend online training programs for oracle so a to knowledgeable of the latest inventions in the market. One thing that must be acknowledged is the fact that technology changes every second of the day with new research being conducted twenty fours a day. This can be attributed to the fact that scientists and researches are constantly striving to come up with more effective products and services in the market.
Oracle Backup and Recovery Interview Questions and Answers during telephonic interview:
If one of your control file is missing or corrupted then we have 2 options to recover it. Check alert.log for exact name and location of corrupted control file. Delete it manually and copy from available rest of control file and rename it and start database. Another option is delete corrupted control file and remove name from parameter file/ spfile. After removing said control file from spfile, start your database.
In incremental checkpoint process, CKPT process records lowest Low RBA to the control file to keep advancing the Buffer checkpoint Queue (BCQ) to make easy and fastest Active Checkpoint Queue (ACQ).
We can enable disable recording incremental checkpoint in alert.log .We can enable/disable recording using parameter log_checkpoints_to_alert=true/false.
If your database is running on Oracle 10g/11g/12c version then there is new feature available called Recyclebin. You can recover dropped table from user_recyclebin or dba_recyclebin.
Then you should need to restore backup on your UAT or test database server and enable time based recovery for applying all archives before drop command execution. For an instance, apply archives up to 3:55 PM here.
Yes. You can. It is not recommended because your production database is large database and running 24/7 environment. Restoration and recovery will take downtime. It is better to perform restoration and recovery process on UAT or Test database.
When use LGWR with SYNC, it means once network I/O initiated, LGWR has to wait for completion of network I/O before write processing. LGWR with ASYNC, means LGWR doesn’t wait to finish network I/O and continuing write processing.
Create indexfile of export dump file using import with indexfile command. A text file will be generating with all table and index object name with number of rows. You can confirm your require table object from this text file. If you are using datapump then there is parameter called "sqlfile" in impdp.
There are lots of reason behind increasing size of archives like If more database changes were performed using batch jobs or any special task like merging 2 database or data etc. You can investigate exact root cause using enabling Log Minor utility.
We can perform this recovery in 2 ways. One is open database mode and another is database mount mode. After taking offline lost datafile, we can bring database open and after that restore lost datafile from last backup. After restoration of datafile we can perform datafile level recovery for applying archive logs and make it online. In database mount mode, we can restore datafile from backup and perform datafile recovery using "Recover datafile" command.
During this recovery we are applying all database changes using archives log and make it to up to date. Complete recovery can be done full database level or datafile level or tablespace level. Main concept is to apply all data changes using archive logs and bring database up to recent time.
When we are performing incomplete recovery it means we bring database to past time or rewind period of time using change based, cancel based or time based recovery. These all recovery make database in prior state of database. The forward sequence number already available after performing recovery, due to mismatching of this sequence numbers and prior state of database, it needs to open database with new sequence number of Redo log and archive logs.
Export and datapump dump file doesn't backup or contain any physical structure of database like datafile, control file, redo log file, parameter file, password file. Instead of physical structure, export dump contains logical structure of database like definition of tablespaces, segments, schemas, data of segments etc. Due to these reasons export and datapump dump is called as logical backup.
2 months back, a potential table was dropped by an application developer on our large 24/7 running production database. Immediately he informed us. We have standby database for our production database. We checked that archives didn’t apply to standby database up to dropped timing. We stopped archive applying on standby immediately and open database read only. Took export of dropped table and imported in production database. After finishing appropriate checking of table, again we started archive applying in standby database for refreshing.
Shutdown immediate. Because without shutdown, we can't perform online backup of database, which running on NOARCHIVELOG mode. We should need to take cold backup of database. After clean shutdown database copy of all datafiles, control files, redo log files, password file, parameter files.
This is the sample and Oracle Backup and Recovery interview questions answers of partial part of topic "Backup and Recovery" of the book Oracle DBA Interview Questions. Kendba provides unique career making services for Oracle DBA from start online Oracle Training, Oracle interview questions books, fresher Oracle jobs assistance services.