eGigData analyst interview questions and answers
Data analyst interviews test Excel, SQL, a BI tool and how you turn numbers into decisions. Expect a SQL question and a case about metrics.
11 questions. Read each one, start the timer and answer out loud as if you were in the room, then open the tip. Nothing is recorded.
Walk me through an analysis you did.
What a good answer covers
The business question, the data, how you cleaned it, what you found and what changed because of it.
How do you clean messy data?
What a good answer covers
Remove duplicates, fix formats, handle missing values, check outliers and document every step.
Which tools do you use?
What a good answer covers
Excel, SQL, Power BI or Tableau, and Python with pandas if you know it. Say what you did with each.
When would you use the median instead of the mean?
What a good answer covers
When data is skewed, like salaries or house prices, because a few large values pull the mean up.
Write a query for the top 5 customers by sales.
What a good answer covers
SELECT customer_id, SUM(amount) AS total FROM orders GROUP BY customer_id ORDER BY total DESC LIMIT 5;
What is a pivot table, and when do you use one?
What a good answer covers
A quick way to summarise data by groups, like sales by region and month.
How would you explain a finding to a non-technical manager?
What a good answer covers
Lead with the answer and the action, use one simple chart, and keep the method for questions.
What is the difference between correlation and causation?
What a good answer covers
Two things moving together doesn’t mean one causes the other. Testing or controlled comparisons show cause.
Which KPIs would you track for an online store?
What a good answer covers
Conversion rate, average order value, customer acquisition cost, repeat purchase rate and return rate.
What is A/B testing?
What a good answer covers
Showing two versions to similar groups at random and comparing results to see which works better.
How do you build a dashboard people actually use?
What a good answer covers
Ask what decisions it supports, show few clear metrics, update it automatically and check who uses it.
All 11 questions with answers
1. Walk me through an analysis you did.
The business question, the data, how you cleaned it, what you found and what changed because of it.
2. How do you clean messy data?
Remove duplicates, fix formats, handle missing values, check outliers and document every step.
3. Which tools do you use?
Excel, SQL, Power BI or Tableau, and Python with pandas if you know it. Say what you did with each.
4. When would you use the median instead of the mean?
When data is skewed, like salaries or house prices, because a few large values pull the mean up.
5. Write a query for the top 5 customers by sales.
SELECT customer_id, SUM(amount) AS total FROM orders GROUP BY customer_id ORDER BY total DESC LIMIT 5;
6. What is a pivot table, and when do you use one?
A quick way to summarise data by groups, like sales by region and month.
7. How would you explain a finding to a non-technical manager?
Lead with the answer and the action, use one simple chart, and keep the method for questions.
8. What is the difference between correlation and causation?
Two things moving together doesn’t mean one causes the other. Testing or controlled comparisons show cause.
9. Which KPIs would you track for an online store?
Conversion rate, average order value, customer acquisition cost, repeat purchase rate and return rate.
10. What is A/B testing?
Showing two versions to similar groups at random and comparing results to see which works better.
11. How do you build a dashboard people actually use?
Ask what decisions it supports, show few clear metrics, update it automatically and check who uses it.
Before the interview
- Read the job description twice and match two of your examples to what it asks for.
- Keep printed copies of your resume, ID proof and certificates ready, even for online rounds.
- Know your current CTC, expected salary and notice period. Check typical pay in our salary guide, and compare offers with the in-hand salary calculator.
- Genuine employers never ask you to pay for an interview, training kit or joining. Report anyone who does.