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Google Professional Cloud Database Engineer Practice Test

503 questions with instant explanations, domain breakdown, and wrong-answer analysis. Built for the real exam.

Instant feedback after each answer
Full explanations included
Domain score breakdown
Real exam: 120 min
Pass mark: 720%

Sample questions with explanations

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Q1Plan and manage database infrastructureeasy
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A company runs a production Cloud SQL for PostgreSQL instance used by a web application. The instance experiences intermittent latency spikes during peak hours. You need to diagnose the cause without downtime. Which tool should you use first?

AUse Database Migration Service to failover to a read replica.
Use Cloud SQL Insights to analyze query performance and identify slow queries.Correct
CUse gcloud sql instances describe to check instance configuration.
DUse VPC Flow Logs to analyze network traffic.

Cloud SQL Insights provides built-in query performance monitoring and diagnostics without requiring any downtime. It surfaces slow queries, lock contention, and resource bottlenecks directly from the PostgreSQL engine, making it the ideal first step to identify the root cause of …Read full explanation

Q2Plan and manage database infrastructuremedium
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A company is migrating an on-premises Oracle database to Cloud SQL for PostgreSQL. The database is 2 TB in size and the network bandwidth to Google Cloud is limited to 500 Mbps. The migration window is 48 hours. Which migration strategy should the Database Engineer recommend?

ACreate a VPN tunnel and use pg_dump/pg_restore over the network.
BUse Database Migration Service with continuous replication.
Export the database to flat files, compress, upload to Cloud Storage, then import to Cloud SQL.Correct
DRequest a dedicated interconnect and then migrate.

Option C is correct because the 2 TB database size and 500 Mbps bandwidth yield a theoretical transfer time of approximately 9.5 hours (2 TB * 1024 GB/TB * 8 bits/byte / 500 Mbps / 3600 seconds/hour), which fits within the 48-hour window. However, pg_dump/pg_restore over a VPN (O…Read full explanation

Q3Plan and manage database infrastructurehard
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A financial services company uses Cloud Spanner for transaction processing. They need to ensure zero downtime during a schema change that adds a new column with a default value to a large table. Which approach should the Database Engineer take?

ACreate a new table with the new column, then use a fan-out pattern to write to both tables until the old table is deprecated.
BUse an ALTER TABLE statement during a maintenance window.
CDrop the table and recreate it with the new schema.
Use ALTER TABLE to add the column; Spanner handles schema changes online.Correct

Option D is correct because Cloud Spanner supports online schema changes, including adding columns with default values, without requiring a maintenance window or causing downtime. Spanner applies schema updates asynchronously across all nodes while the database remains fully avai…Read full explanation

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