Exam Professional Cloud Database Engineer topic 1 question 36 discussion

https://cloud.google.com/spanner/docs/pitr#ways-to-recover To recover the entire database, backup or export the database specifying a timestamp in the past and then restore or import it to a new database. This is typically used to recover from data corruption issues when you have to revert the entire database to a point-in-time before the corruption occurred. This part describes significant corruption - A To recover a portion of the database, perform a stale read specifying a query-condition and timestamp in the past, and then write the results back into the live database. This is typically used for surgical operations on a live database. For example, if you accidentally delete a particular row or incorrectly update a subset of data, you can recover it with this method. This describes insignificant corruption case - E

A, E. The answers are split between significant and insignificant. For insignificant, the simplest form of recovery would be E. That eliminates D. For significant, let’s assume that means a lot of data of the the 50 TB total. A stale read and write back would probably been too onerous, so that eliminates B. That leaves A and C. The question doesn’t mention anything about logical backups (export) which suggests a restore from a backup would be appropriate of a large amount of data that needed to be recovered. https://cloud.google.com/spanner/docs/pitr https://cloud.google.com/spanner/docs/backup/restore-backup

AE are correct.

B: If the corruption is significant, perform a stale ***** read and specify a recovery timestamp. Write the results back. D: If the corruption is insignificant, use backup and ***** restore, and specify a recovery timestamp.

B. If the corruption is significant, perform a stale read and specify a recovery timestamp. Write the results back. D. If the corruption is insignificant, use backup and restore, and specify a recovery timestamp.

B. If the corruption is significant, perform a stale read and specify a recovery timestamp. Write the results back. C. If the corruption is significant, use import and export.