- A
Use BigQuery BI Engine to cache results
Why wrong: BI Engine caches query results but does not reduce the amount of data scanned from the base table.
- B
Create a view with WHERE _PARTITIONTIME >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 30 DAY)
Why wrong: While partition pruning may occur, views are expanded at query time and still scan underlying tables. Cost savings are limited compared to materialized views.
- C
Create a materialized view with the date filter
Materialized views precompute and store the filtered results, reducing query cost and improving performance through incremental updates.
- D
Use a scheduled query to copy the last 30 days to a separate table
Why wrong: This adds complexity and latency; the copy job consumes resources and the separate table requires management.
PCDE Practice Question: Define data structures and implement SQL for Business Intelligence
This PCDE practice question tests your understanding of define data structures and implement sql for business intelligence. 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 has a BigQuery dataset with many views. They need to ensure that only the latest 30 days of data is used in BI reports for performance. The source table is partitioned by ingestion_time. Which approach reduces query cost and improves performance?
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
Create a materialized view with the date filter
Option C is correct because a materialized view precomputes and stores the filtered result set, allowing BigQuery to serve BI queries directly from the materialized view's storage without scanning the entire source table. This eliminates the need to re-process the full table on every query, significantly reducing query cost and improving performance for the 30-day sliding window.
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.
- ✗
Use BigQuery BI Engine to cache results
Why it's wrong here
BI Engine caches query results but does not reduce the amount of data scanned from the base table.
- ✗
Create a view with WHERE _PARTITIONTIME >= TIMESTAMP_SUB(CURRENT_TIMESTAMP(), INTERVAL 30 DAY)
Why it's wrong here
While partition pruning may occur, views are expanded at query time and still scan underlying tables. Cost savings are limited compared to materialized views.
- ✓
Create a materialized view with the date filter
Why this is correct
Materialized views precompute and store the filtered results, reducing query cost and improving performance through incremental updates.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Use a scheduled query to copy the last 30 days to a separate table
Why it's wrong here
This adds complexity and latency; the copy job consumes resources and the separate table requires management.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Google Cloud often tests the distinction between standard views (which are just saved queries) and materialized views (which store results), leading candidates to incorrectly choose a standard view with a WHERE clause, thinking it will reduce cost, when in fact it does not reduce data scanned.
Detailed technical explanation
How to think about this question
Materialized views in BigQuery are automatically refreshed based on the base table's change history, using incremental updates when possible, which avoids full recomputation. The sliding window filter on _PARTITIONTIME ensures that only the most recent 30 partitions are stored, and BigQuery's query engine can read directly from the materialized view's clustered storage, often with zero bytes processed from the base table. In real-world scenarios, this is critical for dashboards that require sub-second response times on terabytes of data, as the materialized view acts as a pre-aggregated, continuously updated snapshot.
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 startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.
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.
- →
Define data structures and implement SQL for Business Intelligence — study guide chapter
Learn the concepts, then practise the questions
- →
Define data structures and implement SQL for Business Intelligence practice questions
Targeted practice on this topic area only
- →
All PCDE questions
503 questions across all exam domains
- →
Google Professional Cloud Database Engineer study guide
Full concept coverage aligned to exam objectives
- →
PCDE practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PCDE practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Plan and manage database infrastructure practice questions
Practise PCDE questions linked to Plan and manage database infrastructure.
Define data structures and implement SQL for Business Intelligence practice questions
Practise PCDE questions linked to Define data structures and implement SQL for Business Intelligence.
Design and implement database schemas practice questions
Practise PCDE questions linked to Design and implement database schemas.
Monitor and optimize database performance practice questions
Practise PCDE questions linked to Monitor and optimize database performance.
PCDE fundamentals practice questions
Practise PCDE questions linked to PCDE fundamentals.
PCDE scenario practice questions
Practise PCDE questions linked to PCDE scenario.
PCDE troubleshooting practice questions
Practise PCDE questions linked to PCDE troubleshooting.
Practice this exam
Start a free PCDE 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 PCDE question test?
Define data structures and implement SQL for Business Intelligence — This question tests Define data structures and implement SQL for Business Intelligence — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Create a materialized view with the date filter — Option C is correct because a materialized view precomputes and stores the filtered result set, allowing BigQuery to serve BI queries directly from the materialized view's storage without scanning the entire source table. This eliminates the need to re-process the full table on every query, significantly reducing query cost and improving performance for the 30-day sliding window.
What should I do if I get this PCDE 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: Jun 30, 2026
This PCDE 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 PCDE 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.