hardMultiple ChoiceObjective-mapped
Google PCA Practice Question: A global e-commerce platform uses Cloud Spanner…
A global e-commerce platform uses Cloud Spanner for product inventory and wants to reduce costs. They notice that read replicas are underutilized and that most queries are single-key reads. Which configuration change will reduce costs while maintaining availability?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Downgrade the instance to a smaller regional configuration with fewer nodes
For Spanner, read replicas are used for read-only workloads; if underutilized, reducing the number of read replicas can lower costs without affecting write availability. However, fine-grained instance configuration changes are not straightforward; the best option is to adjust the number of nodes or use a smaller instance class. But among options, choosing a smaller regional configuration (fewer nodes) is practical.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Use Cloud SQL for reads and Spanner for writes only
Why it's wrong here
This would require application changes and adds complexity, not a simple configuration change.
- ✓
Downgrade the instance to a smaller regional configuration with fewer nodes
Why this is correct
Reducing nodes lowers cost; Spanner automatically redistributes data. This is a valid way to reduce costs.
- ✗
Switch to a multi-region configuration with witness nodes
Why it's wrong here
Multi-region increases cost, not reduces.
- ✗
Reduce the number of read replicas in the instance configuration
Why it's wrong here
Spanner does not have separate read replicas; it uses nodes that handle both reads and writes.
Go deeper
Related to this question
Learn chapter
Introduction to Google Cloud Platform
Key term
Spanner
Google Cloud's globally distributed, strongly consistent, and horizontally scalable database service designed for mission-critical, transactional workloads.
Key term
Regional
Regional refers to a deployment strategy where cloud resources are distributed across multiple geographic areas to improve availability, reduce latency, and meet compliance requirements.
About these practice questions
This PCA question is part of Courseiva's 955-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This PCA practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the PCA exam.