← PCDOE·Google Cloud

Question 676 of 1,000

Manage Database Solutions →hardMultiple ChoiceObjective-mapped

PCDOE Manage Database Solutions Practice Question

This PCDOE practice question tests your understanding of manage database solutions. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. 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 Cloud Spanner database has a table with a primary key and a secondary index. The application frequently queries using a filter on the secondary index column and orders by the primary key. The queries are slow. What should the database administrator do to improve query performance?

Clue words in this question

Noticing these words before you look at the options changes how you read each choice.

Clue: "primary"
Why it matters: Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.

A
Increase the number of nodes to improve query throughput
Why wrong: Scaling nodes improves throughput but does not optimise a specific slow query.
B
Create an interleaved table that mirrors the data
Why wrong: Interleaved tables are for parent-child relationships, not for query optimisation.
C
Create a covering index using CREATE INDEX with the STORING clause to include the required columns
A covering index includes all columns needed for the query, allowing Spanner to avoid accessing the base table, which can improve performance.
D
Use ALTER TABLE to add a new index on the filter column
Why wrong: ALTER TABLE cannot add an index; you must use CREATE INDEX.

Full breakdown with real-world context →

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 covering index using CREATE INDEX with the STORING clause to include the required columns

Cloud Spanner can use a secondary index to filter, but if the ordering is by the primary key, it may need to sort after fetching. A covering index that includes both the filter column and the primary key (or other required columns) can avoid back-and-forth to the table. Storing the primary key in the index is automatic in Spanner (as it is part of the row), but the index may not be ordered by primary key. Adding an interleaved table changes the schema. Increasing nodes adds capacity but doesn't fix the query plan. Using a STORING clause to include extra columns is helpful, but the main issue is ordering. Actually, in Spanner, if you have an index on column A and you order by primary key, Spanner may need to sort. To avoid sorting, you could create a custom index that includes both the filter column and the ordering column (primary key). So option D (create a new index with the filter column and include the primary key as a stored column) might help, but primary key is already included. The correct answer is to create a covering index that includes all columns needed, so Spanner can avoid accessing the base table. Option B (CREATE INDEX ... STORING ...) is the correct way to create a covering index. Option C (ALTER TABLE ... ADD INDEX) is not valid syntax. Option A (increase number of nodes) is for throughput, not query optimization.

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.

✗
Increase the number of nodes to improve query throughput
Why it's wrong here
Scaling nodes improves throughput but does not optimise a specific slow query.
✗
Create an interleaved table that mirrors the data
Why it's wrong here
Interleaved tables are for parent-child relationships, not for query optimisation.
✓
Create a covering index using CREATE INDEX with the STORING clause to include the required columns
Why this is correct
A covering index includes all columns needed for the query, allowing Spanner to avoid accessing the base table, which can improve performance.
Clue confirmation
The clue word "primary" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
Use ALTER TABLE to add a new index on the filter column
Why it's wrong here
ALTER TABLE cannot add an index; you must use CREATE INDEX.

Common exam traps

Common exam trap: answer the scenario, not the keyword

Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.

Detailed technical explanation

How to think about this question

This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.

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.
Use explanations to understand the rule behind the answer.

TExam Day Tips

Underline the problem statement mentally.
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 PCDOE exam domain this question belongs to, then review the specific concept being tested. Practise related questions in that domain and focus on understanding why each wrong answer is tempting — not just why the correct answer is right.

Related PCDOE practice-question pages

Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.

Design and Plan Database Solutions practice questions

Practise PCDOE questions linked to Design and Plan Database Solutions.

Manage Database Solutions practice questions

Practise PCDOE questions linked to Manage Database Solutions.

Migrate Database Solutions practice questions

Practise PCDOE questions linked to Migrate Database Solutions.

Design for Reliability, Scalability, and Disaster Recovery practice questions

Practise PCDOE questions linked to Design for Reliability, Scalability, and Disaster Recovery.

Bootstrapping a Google Cloud organization for DevOps practice questions

Practise PCDOE questions linked to Bootstrapping a Google Cloud organization for DevOps.

Managing service incidents practice questions

Practise PCDOE questions linked to Managing service incidents.

Managing Google Cloud costs practice questions

Practise PCDOE questions linked to Managing Google Cloud costs.

Building and implementing CI/CD pipelines practice questions

Practise PCDOE questions linked to Building and implementing CI/CD pipelines.

Implementing service monitoring strategies practice questions

Practise PCDOE questions linked to Implementing service monitoring strategies.

Optimizing service performance practice questions

Practise PCDOE questions linked to Optimizing service performance.

PCDOE fundamentals practice questions

Practise PCDOE questions linked to PCDOE fundamentals.

PCDOE scenario practice questions

Practise PCDOE questions linked to PCDOE scenario.

Practice this exam

Start a free PCDOE practice session

Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.

10 questions 20 questions 30 questions 50 questions Timed 30

PCDOE practice-test guide →Study guide →Browse all practice tests

FAQ

Questions learners often ask

What does this PCDOE question test?

Manage Database Solutions — This question tests Manage Database Solutions — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Create a covering index using CREATE INDEX with the STORING clause to include the required columns — Cloud Spanner can use a secondary index to filter, but if the ordering is by the primary key, it may need to sort after fetching. A covering index that includes both the filter column and the primary key (or other required columns) can avoid back-and-forth to the table. Storing the primary key in the index is automatic in Spanner (as it is part of the row), but the index may not be ordered by primary key. Adding an interleaved table changes the schema. Increasing nodes adds capacity but doesn't fix the query plan. Using a STORING clause to include extra columns is helpful, but the main issue is ordering. Actually, in Spanner, if you have an index on column A and you order by primary key, Spanner may need to sort. To avoid sorting, you could create a custom index that includes both the filter column and the ordering column (primary key). So option D (create a new index with the filter column and include the primary key as a stored column) might help, but primary key is already included. The correct answer is to create a covering index that includes all columns needed, so Spanner can avoid accessing the base table. Option B (CREATE INDEX ... STORING ...) is the correct way to create a covering index. Option C (ALTER TABLE ... ADD INDEX) is not valid syntax. Option A (increase number of nodes) is for throughput, not query optimization.

What should I do if I get this PCDOE question wrong?

Are there clue words in this question I should notice?

Yes — watch for: "primary". Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.

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 →

How Courseiva writes practice questions · Editorial policy

Last reviewed: Jul 4, 2026

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.

Loading comments…

This PCDOE 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 PCDOE exam.