KQL Where Operator — Filtering Results in Azure Data Explorer | Azure Data Engineer Associate Explained
This DP-203 practice question tests your understanding of develop data processing. 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. A key principle to apply: where operator. 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.
Exhibit
Refer to the exhibit. The following is a KQL query run in Azure Data Explorer:
let T = datatable(Id:int, Name:string, Age:int)
[
1, 'Alice', 30,
2, 'Bob', 25,
3, 'Charlie', 35
];
T
| where Age > 25
| project Name, Age
Refer to the exhibit. You run the KQL query in Azure Data Explorer. What is the output?
Exhibit
Refer to the exhibit. The following is a KQL query run in Azure Data Explorer:
let T = datatable(Id:int, Name:string, Age:int)
[
1, 'Alice', 30,
2, 'Bob', 25,
3, 'Charlie', 35
];
T
| where Age > 25
| project Name, Age
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Name: Alice, Age: 30; Name: Charlie, Age: 35
The KQL query uses a `where` clause to filter rows where Age is greater than 25, which selects Alice (Age 30) and Charlie (Age 35) and excludes Bob (Age 25). The `project` operator then selects only the Name and Age columns, so the output consists of those two rows with those columns.
Key principle: where operator
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
Common exam trap: answer the scenario, not the keyword
A common mistake is to include the 'Id' column in the output, thinking it is retained by the 'project' operator, but 'project' only includes the specified columns. Option B incorrectly includes Id.
Detailed technical explanation
How to think about this question
The `take` operator in KQL is equivalent to `limit` in SQL and returns a specified number of rows without any guarantee of order unless an `order by` clause is used. In Azure Data Explorer, data is stored in extents (shards), and `take` returns rows from the first extent it scans, which can vary across executions. This behavior is important for debugging or sampling data, but for deterministic results, always pair `take` with `order by`.
KKey Concepts to Remember
where operator
project operator
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
where operator
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. where operator Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this DP-203 question in full detail.
Develop data processing — This question tests Develop data processing — where operator.
What is the correct answer to this question?
The correct answer is: Name: Alice, Age: 30; Name: Charlie, Age: 35 — The KQL query uses a `where` clause to filter rows where Age is greater than 25, which selects Alice (Age 30) and Charlie (Age 35) and excludes Bob (Age 25). The `project` operator then selects only the Name and Age columns, so the output consists of those two rows with those columns.
What should I do if I get this DP-203 question wrong?
Review where operator, then practise related DP-203 questions on the same topic to reinforce the concept.
What is the key concept behind this question?
where operator
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 →
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.
This DP-203 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-203 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.