- A
Cloud SQL (MySQL) with cross-region read replicas
Why wrong: Cloud SQL does not provide strong consistency across regions; replicas are eventually consistent.
- B
Cloud Spanner
Spanner offers global strong consistency, external consistency, 99.999% SLA, and sub-10ms writes.
- C
BigQuery multi-region
Why wrong: BigQuery is for analytics, not transactional OLTP.
- D
Cloud Bigtable multi-cluster routing
Why wrong: Bigtable offers eventual consistency across clusters, not strong consistency.
Question 57 of 1,000
PDE Storing the Data Practice Question
This PDE practice question tests your understanding of storing the data. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A company runs a global financial application requiring strong consistency across continents with 99.999% availability. They need to store transaction data with ACID properties and sub-10ms write latency from any region. Which storage service meets all requirements?
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
✓
Cloud Spanner
Cloud Spanner is the only service that provides ACID transactions, strong consistency across continents, and 99.999% availability with sub-10ms write latency. It uses synchronous replication with Paxos-based consensus to ensure consistent writes globally, meeting the strict requirements of a global financial application.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Cloud SQL (MySQL) with cross-region read replicas
Why it's wrong here
Cloud SQL does not provide strong consistency across regions; replicas are eventually consistent.
- ✓
Cloud Spanner
Why this is correct
Spanner offers global strong consistency, external consistency, 99.999% SLA, and sub-10ms writes.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
BigQuery multi-region
Why it's wrong here
BigQuery is for analytics, not transactional OLTP.
- ✗
Cloud Bigtable multi-cluster routing
Why it's wrong here
Bigtable offers eventual consistency across clusters, not strong consistency.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the misconception that cross-region read replicas (like Cloud SQL) can provide strong consistency globally, but they are asynchronous and only offer eventual consistency, failing ACID requirements for transactional writes.
Detailed technical explanation
How to think about this question
Cloud Spanner achieves global strong consistency by using a TrueTime API (based on GPS and atomic clocks) to assign commit timestamps, ensuring linearizability across regions. Under the hood, each write is replicated to a majority of Paxos participants in multiple zones, guaranteeing durability and consistency even during regional failures. In practice, a global financial application must avoid the 'split-brain' scenario that can occur with asynchronous replication, which Spanner's synchronous commit protocol prevents.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Storing the Data — study guide chapter
Learn the concepts, then practise the questions
- →
Storing the Data practice questions
Targeted practice on this topic area only
- →
All PDE questions
1,000 questions across all exam domains
- →
Google Professional Data Engineer study guide
Full concept coverage aligned to exam objectives
- →
PDE practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PDE practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Designing Data Processing Systems practice questions
Practise PDE questions linked to Designing Data Processing Systems.
Ingesting and Processing the Data practice questions
Practise PDE questions linked to Ingesting and Processing the Data.
Storing the Data practice questions
Practise PDE questions linked to Storing the Data.
Preparing and Using Data for Analysis practice questions
Practise PDE questions linked to Preparing and Using Data for Analysis.
Maintaining and Automating Data Workloads practice questions
Practise PDE questions linked to Maintaining and Automating Data Workloads.
Building and operationalizing data processing systems practice questions
Practise PDE questions linked to Building and operationalizing data processing systems.
Operationalizing machine learning models practice questions
Practise PDE questions linked to Operationalizing machine learning models.
Ensuring solution quality practice questions
Practise PDE questions linked to Ensuring solution quality.
PDE fundamentals practice questions
Practise PDE questions linked to PDE fundamentals.
PDE scenario practice questions
Practise PDE questions linked to PDE scenario.
PDE troubleshooting practice questions
Practise PDE questions linked to PDE troubleshooting.
Practice this exam
Start a free PDE practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this PDE question test?
Storing the Data — This question tests Storing the Data — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Cloud Spanner — Cloud Spanner is the only service that provides ACID transactions, strong consistency across continents, and 99.999% availability with sub-10ms write latency. It uses synchronous replication with Paxos-based consensus to ensure consistent writes globally, meeting the strict requirements of a global financial application.
What should I do if I get this PDE question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jul 4, 2026
This PDE 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 PDE exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.