- A
BigQuery
Why wrong: BigQuery is an analytics warehouse, not designed for OLTP workloads or PostgreSQL compatibility.
- B
Cloud Spanner
Why wrong: Spanner is not PostgreSQL-compatible; it uses proprietary SQL.
- C
Cloud SQL for PostgreSQL
Why wrong: Cloud SQL does not have a columnar engine for analytics; analytical queries would be slow.
- D
AlloyDB
AlloyDB is PostgreSQL-compatible and uses a columnar engine to accelerate analytical queries while supporting OLTP.
Question 793 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 is migrating an on-premises PostgreSQL database to Google Cloud. The database runs complex analytical queries mixed with OLTP workloads. They need PostgreSQL compatibility and want to improve analytical query performance without changing the application. Which database 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 demanding transactional and analytical workloads. It combines the PostgreSQL ecosystem with a columnar engine and adaptive caching to accelerate analytical queries by up to 100x over standard PostgreSQL, all without requiring application changes. This makes it ideal for mixed OLTP and complex analytical queries while maintaining 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.
- ✗
BigQuery
Why it's wrong here
BigQuery is an analytics warehouse, not designed for OLTP workloads or PostgreSQL compatibility.
- ✗
Cloud Spanner
Why it's wrong here
Spanner is not PostgreSQL-compatible; it uses proprietary SQL.
- ✗
Cloud SQL for PostgreSQL
Why it's wrong here
Cloud SQL does not have a columnar engine for analytics; analytical queries would be slow.
- ✓
AlloyDB
Why this is correct
AlloyDB is PostgreSQL-compatible and uses a columnar engine to accelerate analytical queries while supporting OLTP.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often choose Cloud SQL for PostgreSQL because it is the most familiar PostgreSQL option, overlooking that AlloyDB is specifically engineered for mixed OLTP and analytical workloads with PostgreSQL compatibility, while Cloud SQL lacks the advanced analytical acceleration features.
Detailed technical explanation
How to think about this question
AlloyDB achieves its analytical performance boost through a columnar engine that automatically offloads analytical queries from the standard PostgreSQL row-based storage, and an adaptive cache that learns access patterns to pre-warm data in memory. Under the hood, it uses a disaggregated storage architecture with a high-speed cache layer, allowing it to handle mixed workloads without the need for separate read replicas or ETL processes. In a real-world scenario, a company running complex reporting queries alongside user-facing transactions on the same PostgreSQL database would see query times drop from minutes to seconds with AlloyDB, while Cloud SQL would require manual tuning or additional replicas to achieve similar results.
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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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 demanding transactional and analytical workloads. It combines the PostgreSQL ecosystem with a columnar engine and adaptive caching to accelerate analytical queries by up to 100x over standard PostgreSQL, all without requiring application changes. This makes it ideal for mixed OLTP and complex analytical queries while maintaining 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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