Question 1mediummultiple choice
Full question →mediummultiple choiceObjective-mapped
A company uses Azure SQL Database to store order data. The Orders table has millions of rows with columns: OrderID (primary key, clustered), CustomerID, OrderDate, Status, TotalAmount. Queries frequently filter on OrderDate and Status, and sort results by OrderDate descending. Which indexing strategy will most improve query performance for these filters and sort?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Distractor review
Create a clustered index on OrderDate
Changing the clustered index to OrderDate would improve range scans on OrderDate but the clustered index physically orders the data; however, the primary key OrderID would then be a nonclustered index, which may affect other queries. A composite nonclustered index is more targeted.
B
Best answer
Create a nonclustered index on (OrderDate DESC, Status) and include TotalAmount
This composite index covers both filter columns in the correct sort order and includes the TotalAmount column, making the query fully covered without needing to access the table. This yields the best performance for the described queries.
C
Distractor review
Create a nonclustered index on Status alone
A single-column index on Status helps filter by Status, but the query also filters on OrderDate and sorts by OrderDate. Without an index on OrderDate, the database must perform a sort after filtering, which is slower.
D
Distractor review
Create a clustered columnstore index on the table
Columnstore indexes are designed for analytical queries that aggregate large volumes of data, not for point queries or range scans with sort on a specific date range. They are not optimal for this OLTP-style query.
Common exam trap
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.
Technical deep dive
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.
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.
More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
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FAQ
Questions learners often ask
What does this DP-900 question test?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: Create a nonclustered index on (OrderDate DESC, Status) and include TotalAmount — To optimize queries filtering on both OrderDate and Status and sorting by OrderDate descending, a composite nonclustered index on (OrderDate DESC, Status) INCLUDE (TotalAmount) would provide the best performance. The index can be used for the filter and sort without touching the table. A clustered index on OrderID (the primary key) does not help for these filter columns. A nonclustered index on Status alone requires a separate sort. A columnstore index is optimized for large aggregations, not point lookups or range scans with sort.
What should I do if I get this DP-900 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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