Exam Professional Cloud Database Engineer topic 1 question 74 discussion

https://cloud.google.com/database-migration/docs/postgres/known-limitations

If encrypted databases require customer-managed encryption keys to decrypt the databases, and if Database Migration Service doesn't have access to the keys, then the databases can't be migrated. However, if customer data is encrypted by the pgcrypto extension, then the data can be migrated with Database Migration Service (because Cloud SQL supports the extension).

https://cloud.google.com/database-migration/docs/postgres/known-limitations: If encrypted databases require customer-managed encryption keys to decrypt the databases, and if Database Migration Service doesn't have access to the keys, then the databases can't be migrated. For tables that don't have primary keys, Database Migration Service supports migration of the initial snapshot and INSERT statements during the change data capture (CDC) phase. You should migrate UPDATE and DELETE statements manually.

PKs (needed) and pgcrypto extension (confirm if enabled) to assess limitations during migration

From this link (https://cloud.google.com/database-migration/docs/postgres/known-limitations), correct answers should be B and D. Excerpts supporting these choices: "For tables that don't have primary keys, Database Migration Service supports migration of the initial snapshot and INSERT statements during the change data capture (CDC) phase. You should migrate UPDATE and DELETE statements manually." "If encrypted databases require customer-managed encryption keys to decrypt the databases, and if Database Migration Service doesn't have access to the keys, then the databases can't be migrated. However, if customer data is encrypted by the pgcrypto extension, then the data can be migrated with Database Migration Service (because Cloud SQL supports the extension)." Therefore, for the migration to be executable: * Only tables with a primary key can be migrated; * Only data encrypted by the pgcrypto extension can be migrated.

The correct answer is B & D. option E (customer-managed encryption keys) is not directly related to the limitations of Database Migration Service for PostgreSQL to Cloud SQL.

B, E. A is irrelevant. So is C. Cloud SQL supports the pgcrypto extension so that’s also irrelevant. That leaves B and E. The link provided by chelbsik is spot on.

B: Identify all tables that do not have a ***** primary key. Tables in databases that don't have a primary key aren't migrated automatically by Database Migration Service. You must manually migrate them. The Migrating tables without a primary key section outlines different strategies. E: Identify whether the source database uses customer-managed encryption ***** keys (CMEK).