- A
Cloud Spanner
Why wrong: Spanner is globally distributed but not specifically optimised for hybrid analytics.
- B
Cloud SQL for PostgreSQL
Why wrong: Cloud SQL is for transactional workloads; columnar analytics performance is limited.
- C
BigQuery
Why wrong: BigQuery is analytics-only, not transactional.
- D
AlloyDB
Correct: AlloyDB has a columnar engine for analytics and is PostgreSQL-compatible.
Question 127 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 wants to run hybrid transactional and analytical workloads on a PostgreSQL-compatible database with high performance. Which service should they choose?
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
✓
AlloyDB
AlloyDB is the correct choice because it is a fully managed PostgreSQL-compatible database service specifically designed for high-performance hybrid transactional and analytical workloads. It combines transactional processing with built-in columnar analytics, delivering up to 4x faster transactional performance and up to 100x faster analytical queries than standard PostgreSQL, without requiring any schema changes or ETL.
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 Spanner
Why it's wrong here
Spanner is globally distributed but not specifically optimised for hybrid analytics.
- ✗
Cloud SQL for PostgreSQL
Why it's wrong here
Cloud SQL is for transactional workloads; columnar analytics performance is limited.
- ✗
BigQuery
Why it's wrong here
BigQuery is analytics-only, not transactional.
- ✓
AlloyDB
Why this is correct
Correct: AlloyDB has a columnar engine for analytics and is PostgreSQL-compatible.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Google often tests the distinction between 'PostgreSQL-compatible' and 'PostgreSQL-based' — candidates mistakenly choose Cloud SQL for PostgreSQL because it is a managed PostgreSQL service, but they overlook the specific requirement for hybrid transactional and analytical workloads, which AlloyDB uniquely addresses with its integrated columnar engine.
Detailed technical explanation
How to think about this question
AlloyDB achieves its performance through a disaggregated storage architecture with a columnar engine that automatically offloads analytical queries from the transactional node, using a log-structured merge tree (LSM) approach for writes and a vectorized execution engine for analytics. Under the hood, it leverages a distributed file system called AlloyDB Storage, which separates compute from storage and uses a write-ahead log (WAL) to ensure ACID compliance while enabling near-real-time analytics on the same data. In a real-world scenario, an e-commerce platform can run OLTP transactions (e.g., order placement) and complex analytical queries (e.g., sales trends) on the same AlloyDB instance without data duplication or ETL pipelines.
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 cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
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: AlloyDB — AlloyDB is the correct choice because it is a fully managed PostgreSQL-compatible database service specifically designed for high-performance hybrid transactional and analytical workloads. It combines transactional processing with built-in columnar analytics, delivering up to 4x faster transactional performance and up to 100x faster analytical queries than standard PostgreSQL, without requiring any schema changes or ETL.
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.
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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 →
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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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