Interview Questions and Answers

Physical stand-by is a standby database that is an exact replica of the primary database, while snapshot standby is a read-only standby database that allows for testing and reporting.

• Physical stand-by is an exact replica of the primary database, maintained through redo apply.

• Snapshot standby is a read-only standby database that allows for testing and reporting.

• Snapshot standby can be converted back to a physical stand-by database if needed.

Configuration parameters play a crucial role in setting up Data Guard for Oracle databases.

• LOG_ARCHIVE_DEST_1 and LOG_ARCHIVE_DEST_2 are used to specify the locations where archived redo logs are stored.

• FAL_SERVER and FAL_CLIENT parameters are used for automatic recovery in case of a failover.

• DB_UNIQUE_NAME parameter is used to uniquely identify each database in a Data Guard configuration.

• LOG_ARCHIVE_CONFIG parameter is used to specify the configuration for archiving redo log...read more

Issues faced during datapatch include conflicts with existing patches, errors during patching process, and compatibility issues.

• Conflicts with existing patches can cause datapatch to fail

• Errors during the patching process may require troubleshooting and reapplying the patch

• Compatibility issues with the database version or components can lead to issues with datapatch

Transaction log is a file that records all changes made to a database, allowing for recovery in case of system failure.

• Records all changes made to the database

• Allows for recovery in case of system failure

• Helps maintain data integrity

• Can be used for point-in-time recovery

• Examples: redo log in Oracle, transaction log in SQL Server

SMON (System Monitor) process is a background process in Oracle database responsible for instance recovery and cleanup tasks.

• SMON process performs crash recovery when an instance crashes

• It coalesces free space in the database by merging adjacent free extents

• SMON process also cleans up temporary segments that are no longer in use

• It updates the data dictionary cache with the latest information

Top faced issue is the most common and critical problem faced in a particular field.

• Examples: database crashes, data loss, security breaches, performance issues

• It is important to have a plan in place to address top faced issues

• Regular monitoring and maintenance can help prevent top faced issues

Restoration steps in RAC involve restoring the database files, recovering the database, and reconfiguring the RAC environment.

• Restore the database files from backup using RMAN

• Recover the database using RMAN

• Reconfigure the RAC environment by starting the instances and services