Google Professional Cloud Database Engineer Question 250
Select 3Google Cloud PlatformYour team is running an e-commerce application on Cloud SQL for PostgreSQL. The application's read traffic has significantly increased, causing performance issues. You need to assess the requirements for adding read replicas to handle the traffic. Which factors should you consider before deploying read replicas?
- A
The application's tolerance for eventual consistency in read operations
- B
The network latency between the primary instance and the read replicas
- C
The ability to perform writes directly on the read replicas
- D
The maximum number of read replicas supported by Cloud SQL for PostgreSQL
- E
The storage type used by the primary instance (e.g., SSD or HDD)
Show answer and explanation
Correct answers: A, B, D
Explanation
When assessing requirements for read replicas, it is crucial to consider eventual consistency since replicas are asynchronously updated and may lag behind the primary instance. Additionally, network latency affects the performance of replicas, and knowing the platform's limitations on the number of replicas is essential for scalability. Writes are not supported on read replicas, and the storage type of the primary instance does not directly influence read replica deployment.
- A. Correct.
Read replicas are asynchronously updated, which means there is a delay between the primary instance and the replicas. Applications must tolerate eventual consistency for read operations.
- B. Correct.
Network latency between the primary instance and read replicas can impact the synchronization time and the performance of read queries. It's important to assess this factor.
- C. Incorrect.
Writes cannot be performed directly on read replicas. They are meant for read-only operations, so this is not a valid consideration.
- D. Correct.
Cloud SQL for PostgreSQL has a limit on the maximum number of read replicas that can be created. Knowing this limit is important to ensure scalability.
- E. Incorrect.
The storage type of the primary instance does not directly affect the deployment of read replicas. While storage performance impacts the primary instance, it is not a key factor for assessing read replica requirements.