Oracle 1z0-908 Questions Answers

Post-upgrade table storage requirements after logical upgrades are usually smaller than that after physical upgrades.

Physical upgrades are performed for current instances on bare metal deployments, whereas logical upgrades are used for virtual machines or containerized instances.

Logical upgrades are much faster because they do not require restarting the mysqld process.

Post-upgrade table storage requirements after physical upgrades are usually smaller than that after logical upgrades.

Physical upgrades are much faster because they do not require restarting the mysqld process.

Physical upgrades leave data in place, whereas logical upgrades require data to be restored from mysqldump-type backups taken before the upgrades.

Snapshot-based backups greatly reduce time during which the database and applications are unavailable.

There is no need for InnoDB tables to perform its own recovery when restoring from the snapshot backup.

The frozen file system can be cloned to another virtual machine immediately into active service.

A separate physical copy must be made before releasing the snapshot backup.

Snapshot backups can be used only in virtual machines.

Updating index statistics is an I/O expensive operation.

Index statistics are calculated from pages buffered in the buffer pool for tables with InnoDB storage engine.

Setting innodb_stats_auto_recalc=ON causes statistics to be updated automatically when a new index is created.

Execution plans based on transient index statistics improve precision when

innodb_stats_persistent_sample_pages is increased.

Increasing innodb_stats_persistent_sample_pages determines higher pages scanning speed, at the cost of increased memory usage.

Tables are scanned and index statistics recalculated when an instance is restarted.

Increase the number of buffer pool instances to 16.

Increase the number of buffer pool instances to 32.

Decrease the number of buffer pool instances to 1.

Increase the number of buffer pool instances to 12.

Decrease the number of buffer pool instances to 4.