Google Professional Cloud Database Engineer Question 207
Single answerGoogle Cloud PlatformYour organization is planning to migrate a mission-critical on-premises PostgreSQL database to Google Cloud. The team requires near-zero downtime during migration, and the database will also need to remain in sync with the on-premises database until the cutover is complete. Which approach should you implement to meet these requirements?
- A
Use Cloud SQL for PostgreSQL with Database Migration Service (DMS) in continuous replication mode.
- B
Manually export the database using pg_dump, transfer it to Cloud Storage, and then import it into Cloud SQL.
- C
Use Cloud Spanner and configure data replication from PostgreSQL to Cloud Spanner.
- D
Set up a VPN connection and use a custom script to replicate data from the on-premises database to a Cloud SQL instance.
Show answer and explanation
Correct answer: A
Explanation
To achieve a near-zero downtime migration for a PostgreSQL database, Google's Database Migration Service (DMS) is the recommended solution. DMS allows for continuous replication, keeping the destination (Cloud SQL) database updated with changes from the source PostgreSQL database until the final cutover. This ensures minimal service disruption and reliable migration.
- A. Correct.
This is the correct approach. Database Migration Service (DMS) supports near-zero downtime migrations using continuous replication. It can keep the source PostgreSQL database in sync with the Cloud SQL instance until the cutover.
- B. Incorrect.
This approach would result in significant downtime as the data export and import process is not real-time and does not support continuous replication.
- C. Incorrect.
Cloud Spanner is not compatible with PostgreSQL replication. This approach would require significant application changes and doesn't support near-zero downtime migration.
- D. Incorrect.
While a VPN connection might enable connectivity, custom scripts for database replication are error-prone, harder to manage, and do not guarantee near-zero downtime.