- A
Cloud Bigtable
Bigtable is the correct choice: wide-column NoSQL, designed for time-series and IoT workloads, single-digit ms latency, and scales to millions of QPS with additional nodes.
- B
BigQuery
Why wrong: BigQuery is an analytics data warehouse with query latency measured in seconds. It is not designed for millisecond lookups at IoT scale.
- C
Cloud Spanner
Why wrong: Spanner is a globally distributed relational database optimised for ACID transactions, not single-digit ms time-series reads at millions of QPS.
- D
Firestore
Why wrong: Firestore is a document database suited for mobile/web apps with hierarchical data. It does not scale to millions of QPS for time-series workloads.
Question 724 of 1,000
PDE Storing the Data Practice Question
This PDE practice question tests your understanding of storing the data. Compare every option against the stated constraints before choosing — the best answer satisfies all requirements, not just the most obvious one. 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 needs to store petabytes of time-series IoT sensor data and query it with single-digit millisecond latency at millions of reads per second. The data has a simple key-value structure with timestamps. Which Google Cloud database is MOST appropriate?
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 Bigtable
Cloud Bigtable is a fully managed, scalable NoSQL database designed for large analytical and operational workloads, handling petabytes of data with consistent sub-10ms latency at millions of reads per second. Its key-value model with timestamps directly matches the time-series IoT sensor data structure, and it supports high-throughput, low-latency access via the HBase API or Bigtable client libraries.
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 Bigtable
Why this is correct
Bigtable is the correct choice: wide-column NoSQL, designed for time-series and IoT workloads, single-digit ms latency, and scales to millions of QPS with additional nodes.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
BigQuery
Why it's wrong here
BigQuery is an analytics data warehouse with query latency measured in seconds. It is not designed for millisecond lookups at IoT scale.
- ✗
Cloud Spanner
Why it's wrong here
Spanner is a globally distributed relational database optimised for ACID transactions, not single-digit ms time-series reads at millions of QPS.
- ✗
Firestore
Why it's wrong here
Firestore is a document database suited for mobile/web apps with hierarchical data. It does not scale to millions of QPS for time-series workloads.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the distinction between operational databases (Bigtable) and analytical warehouses (BigQuery), so the trap here is assuming that 'petabytes of data' automatically requires a data warehouse like BigQuery, ignoring the real-time, low-latency key-value access pattern that Bigtable is purpose-built for.
Detailed technical explanation
How to think about this question
Under the hood, Cloud Bigtable uses a distributed, sharded storage architecture based on Google's Chubby lock service and SSTables (Sorted String Tables), which enable efficient compression and fast point lookups via row key scans. The timestamped key-value model allows automatic garbage collection of old data based on configurable time-to-live (TTL) policies, making it ideal for IoT sensor data where only recent values are needed. In real-world scenarios, companies like Spotify and Twitter use Bigtable for time-series analytics, achieving consistent single-digit millisecond latency even under heavy write and read loads.
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 company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
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.
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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 Bigtable — Cloud Bigtable is a fully managed, scalable NoSQL database designed for large analytical and operational workloads, handling petabytes of data with consistent sub-10ms latency at millions of reads per second. Its key-value model with timestamps directly matches the time-series IoT sensor data structure, and it supports high-throughput, low-latency access via the HBase API or Bigtable client libraries.
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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