- A
Cloud SQL
Why wrong: PostgreSQL-compatible but no columnar analytics; limited to 10k QPS.
- B
Cloud Bigtable
Why wrong: No SQL, not relational, eventual consistency.
- C
Cloud Spanner
Strong consistency, globally distributed, OLTP+analytics via SQL, PostgreSQL interface available.
- D
BigQuery
Why wrong: OLAP only, not OLTP.
- E
AlloyDB
PostgreSQL-compatible, columnar engine for analytics, strong consistency, high availability.
Question 553 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 global fintech company needs a database that can serve transactional (OLTP) and analytical (OLAP) workloads with strong consistency. They require high availability and PostgreSQL compatibility. Which TWO Google Cloud databases meet these requirements? (Choose 2 correct options)
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 correct because it provides a globally distributed, strongly consistent relational database service that supports both OLTP and OLAP workloads via PostgreSQL-compatible interfaces (including the PostgreSQL dialect). It offers high availability through synchronous replication across zones and regions, and its TrueTime-based atomic clocks ensure external consistency for transactions, meeting the fintech company's requirements for strong consistency and PostgreSQL compatibility.
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
Why it's wrong here
PostgreSQL-compatible but no columnar analytics; limited to 10k QPS.
- ✗
Cloud Bigtable
Why it's wrong here
No SQL, not relational, eventual consistency.
- ✓
Cloud Spanner
Why this is correct
Strong consistency, globally distributed, OLTP+analytics via SQL, PostgreSQL interface available.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
BigQuery
Why it's wrong here
OLAP only, not OLTP.
- ✓
AlloyDB
Why this is correct
PostgreSQL-compatible, columnar engine for analytics, strong consistency, high availability.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the misconception that Cloud SQL or BigQuery can serve both OLTP and OLAP workloads with strong consistency, but Cloud SQL lacks global scaling and OLAP performance, and BigQuery is purely analytical without transactional support.
Detailed technical explanation
How to think about this question
Cloud Spanner uses TrueTime, a globally synchronized clock service based on GPS and atomic clocks, to enforce external consistency for distributed transactions, ensuring that reads and writes are globally ordered. AlloyDB, on the other hand, leverages a columnar engine and adaptive indexing to accelerate analytical queries on transactional data, and it provides PostgreSQL compatibility by being built on the PostgreSQL engine with custom extensions for high availability and performance. In a real-world fintech scenario, Spanner's ability to handle both OLTP and OLAP without separate ETL pipelines reduces operational complexity, while AlloyDB's integration with Google Cloud's Vertex AI enables real-time fraud detection on transactional data.
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
An e-commerce site experiences heavy traffic on Black Friday and near-zero traffic during off-peak weeks. Rather than provisioning permanent large VMs, the team uses auto-scaling groups that add capacity automatically under load and reduce it overnight. Questions like this test whether you understand elasticity, availability zones, and cloud compute scaling patterns.
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
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Storing the Data practice questions
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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 correct because it provides a globally distributed, strongly consistent relational database service that supports both OLTP and OLAP workloads via PostgreSQL-compatible interfaces (including the PostgreSQL dialect). It offers high availability through synchronous replication across zones and regions, and its TrueTime-based atomic clocks ensure external consistency for transactions, meeting the fintech company's requirements for strong consistency and PostgreSQL compatibility.
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.
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