Question 651 of 1,000
Manage Database SolutionsmediumMultiple ChoiceObjective-mapped

PCDOE Manage Database Solutions Practice Question

This PCDOE practice question tests your understanding of manage database solutions. 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 Cloud Spanner database needs a new index added to support a new query pattern. The database is serving live traffic. Which approach should be taken?

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 the index using DDL statement 'CREATE INDEX' — it will be applied online without downtime.

Cloud Spanner supports online schema changes, including index creation, without downtime. The 'CREATE INDEX' DDL statement is applied asynchronously in the background, allowing the database to continue serving live traffic while the index is built. This is the correct approach because it avoids any interruption to the application.

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.

  • Export the data, create a new database with the index, and import the data.

    Why it's wrong here

    This causes significant downtime and is unnecessary.

  • Create the index using DDL statement 'CREATE INDEX' — it will be applied online without downtime.

    Why this is correct

    Correct. Spanner schema changes are non-blocking for existing database operations.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Stop the application, add the index, and restart.

    Why it's wrong here

    Downtime is not required.

  • Use gcloud spanner databases add-index command.

    Why it's wrong here

    No such command; indexes are added via DDL.

Common exam traps

Common exam trap: answer the scenario, not the keyword

Cisco often tests the misconception that schema changes in a distributed database require downtime or manual data migration, leading candidates to choose disruptive options like stopping the application or re-importing data.

Trap categories for this question

  • Command / output trap

    No such command; indexes are added via DDL.

Detailed technical explanation

How to think about this question

Cloud Spanner implements online DDL by creating a new index in the background as a separate partition, using a two-phase process: first, it builds the index data from existing table data, then it atomically switches the schema to include the new index. During this process, writes to the base table are also applied to the index via a shadow pipeline, ensuring consistency without locking the table. This mechanism is based on Spanner's distributed, synchronous replication and TrueTime API, which enable non-blocking schema changes even under heavy write 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 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.

Visual reference

Client Server SYN (seq=100) SYN-ACK (seq=200, ack=101) ACK (ack=201) Connection established — data transfer begins

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.

Related practice questions

Related PCDOE practice-question pages

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

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.

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 the index using DDL statement 'CREATE INDEX' — it will be applied online without downtime. — Cloud Spanner supports online schema changes, including index creation, without downtime. The 'CREATE INDEX' DDL statement is applied asynchronously in the background, allowing the database to continue serving live traffic while the index is built. This is the correct approach because it avoids any interruption to the application.

What should I do if I get this PCDOE 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 →

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…

Sign in to join the discussion.

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.