DA0-002 Data Acquisition and Preparation Practice Question
In a table with columns 'employee_id' and 'manager_id', a data analyst needs to retrieve the hierarchy level of each employee, where the top manager has manager_id NULL. Which SQL feature is best suited?
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
✓
A recursive CTE
Recursive CTE can traverse hierarchical data to compute levels.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
A window function with ROW_NUMBER()
Why it's wrong here
Window functions cannot traverse hierarchical relationships.
- ✓
A recursive CTE
Why this is correct
Recursive CTE can iterate through levels to assign hierarchy depth.
- ✗
A GROUP BY clause with aggregation
Why it's wrong here
GROUP BY aggregates, does not handle hierarchies.
- ✗
A self-join with a LEFT JOIN
Why it's wrong here
A self-join gives only one level, not the entire hierarchy depth.
Go deeper
Related to this question
About these practice questions
This DA0-002 question is part of Courseiva's 986-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This DA0-002 practice question is part of Courseiva's free CompTIA 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 DA0-002 exam.