Question 271 of 982

DP-900 Practice Question: Identify considerations for relational data on Azure

This DP-900 practice question tests your understanding of identify considerations for relational data on azure. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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 hospital uses Azure SQL Database to store patient appointment records. The 'Appointments' table has columns: AppointmentID (primary key), PatientID, DoctorID, AppointmentDate, and Status. Queries frequently filter by DoctorID (equality) and AppointmentDate (range) to retrieve a doctor's schedule. Currently, these queries are slow. Which index strategy will most improve performance for these queries?

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.

Question 1mediummultiple choice
Read the full NAT/PAT explanation →

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

Add a nonclustered index on (DoctorID, AppointmentDate).

Option B is correct because a nonclustered index on (DoctorID, AppointmentDate) supports both equality filtering on DoctorID and range filtering on AppointmentDate. This index structure allows SQL Server to perform a single index seek for the doctor, then a range scan within that doctor's appointments, avoiding a full table scan. The order of columns matters: the leading column (DoctorID) handles the equality predicate, and the second column (AppointmentDate) handles the range predicate efficiently.

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.

  • Add a clustered index on AppointmentID.

    Why it's wrong here

    A clustered index on AppointmentID is useful for queries that search by the primary key, but does not directly support the filter on DoctorID and AppointmentDate.

  • Add a nonclustered index on (DoctorID, AppointmentDate).

    Why this is correct

    This composite index allows the query to first seek on the equality column (DoctorID) and then efficiently scan the range of AppointmentDate within that doctor's rows.

    Clue confirmation

    The clue word "primary" in the question point toward this answer.

    Related concept

    Read the scenario before looking for a memorised answer.

  • Add a columnstore index on the Status column.

    Why it's wrong here

    Columnstore indexes are designed for large fact tables and aggregations, not for filtering single rows or small ranges by multiple columns.

  • Add a nonclustered index on (AppointmentDate, DoctorID).

    Why it's wrong here

    Because AppointmentDate is used with a range filter, placing it first in the index reduces the benefit of the equality filter on DoctorID, likely requiring more index rows to be scanned.

Common exam traps

Common exam trap: answer the scenario, not the keyword

The trap here is that candidates often think the date column should be first because it's a range query, but the correct strategy is to place the equality column first to minimize the scan range, then the range column second for efficient filtering.

Detailed technical explanation

How to think about this question

Under the hood, SQL Server uses a B-tree structure for nonclustered indexes. When the index is ordered by (DoctorID, AppointmentDate), the engine can seek directly to the first row for a given DoctorID and then perform a range scan on AppointmentDate, reading only the relevant rows. In contrast, an index on (AppointmentDate, DoctorID) would require a range scan on the date column first, then a residual predicate check on DoctorID, potentially scanning many more rows. This is a classic example of the 'leading column for equality' rule in composite index design.

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.

Related practice questions

Related DP-900 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 DP-900 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 DP-900 question test?

Identify considerations for relational data on Azure — This question tests Identify considerations for relational data on Azure — Read the scenario before looking for a memorised answer..

What is the correct answer to this question?

The correct answer is: Add a nonclustered index on (DoctorID, AppointmentDate). — Option B is correct because a nonclustered index on (DoctorID, AppointmentDate) supports both equality filtering on DoctorID and range filtering on AppointmentDate. This index structure allows SQL Server to perform a single index seek for the doctor, then a range scan within that doctor's appointments, avoiding a full table scan. The order of columns matters: the leading column (DoctorID) handles the equality predicate, and the second column (AppointmentDate) handles the range predicate efficiently.

What should I do if I get this DP-900 question wrong?

Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.

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: Jun 11, 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 DP-900 practice question is part of Courseiva's free Microsoft 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 DP-900 exam.