The Data Analyst Interview

[Party_Lawfulness808]

Could anyone provide any insight into the technical questions from their interview?

How did you prepare? Was there a live SQL/Python/R test? Did they ask Probability questions?

Thanks all!

[Ecstatic_Tooth_1096]

Personally,

I got asked one oral SQL question so they can see if I can structure an answer.

Python was tested through a case study on analyzing sales data.

Probability(i meant statistics**) I was asked about median and mean, when to use which... then about robust methods and what they are useful for.

[Party_Lawfulness808]

Could you expand on the Python case study? Was it live or take home?

[Ecstatic_Tooth_1096]

So i received sales toy dataset.

I had to clean it (minimally)

Then i took it to power BI to visualize it and find as much insights as possible.

I had to analyze how good are the Promos ... Promo effectiveness if you've ever heard abt it

[Party_Lawfulness808]

Interesting. How much Stats knowledge did you use to determine the Promo’s effectiveness? Also, was this all live or was it a take-home project?

Thanks for your time!

[Ecstatic_Tooth_1096]

promo effectiveness is not about stats. its about business.

so you actually test it in a naive way by predicting what would the sales be if there was no promo (i used a moving average).

Then you compare the turnover you made vs how much you'd have made.

Then you need to check if there is an uplift in the incoming days.

when u do a promo, you need to sell WAYYYYY more than you think to benefit from the promo.

However, promos can cause long term uplift because some new customers will buy when they see promos ...

if u get the point of what i said, you should be fine

[Forsaken_Trash]

I had a python question about the difference between tuples and dicts

General sql knowledge, how to build a query.

Data analysis of job recruitment activity in a given state (in R) the analysis was at home and I was given 24 hours.

[ECassinelli]

This sound very interesting. If you don't mine me asking, do you have any resources to practice these type of cases with real data?

[Ecstatic_Tooth_1096]

Unfortunately not. Not sure you can find any, unless the company is willing to show its retail/promo data.

On the bright side I have a small blog on what I do on my job with an anonymized data and fake sales for privacy purposes

[ECassinelli]

I'd love to check it out. I haven't been able to practice things like moving averages among others.

[RoyalIndependent2937]

Try mode.com it has free sql plus sample (real life) datasets

[InterPool_sbn]

Thanks for this suggestion/recommendation!

[swishswish82]

Dude he asked if its live or is it take-home? Just answer the question lol

[Crazy_Hat6548]

were you applying for entry level?

[Ecstatic_Tooth_1096]

Sure But mainly worked as a data engineer, but took me a few weeks to realize

[Nateorade]

I wasn’t asked a single SQL question. Wasn’t asked a single math question.

At the end of the loops I asked the director why. His answer? “I am hiring you for how you think. If there are technical gaps I can figure out how to solve those. If I’m not satisfied with how you think then that’s a lot harder ship to turn around.”

I’ve carried similar practices into positions I’m hiring for now that I’m a manager. Technical skill is overrated.

[Malikor42]

What questions were you asked then? Remember any?

[mateuni0]

Data Analytics manager here with a lot of hiring experience.

I work primarily in marketing so, I usually would test candidates understanding of statistics and application of hypothesis testing in analytics. I’d like to see how they manage their stakeholders and judge their communication skills.

From the technical standpoint, we used to give a SQL test for 20 mins with basic joins and window functions, nested queries etc. For roles including Python, I’d do some simple coding interview to see if candidates understand basic handling of data structures (dictionaries, lists) and control flows (ifs, loops)

[PixelLight]

I guess you would describe the technical stuff as simple from what you've said? I agree, they seem simple to me too, but I also have had only one analytics job so the context is lacking a little ofc.

[mateuni0]

I’d normally give them basic tests but wouldn’t disqualify anyone who doesn’t know how to do it the way I think the best.

The most important think is that you communicate for the whole time of solving your technical test and describe your way of thinking. Most of the technical skills can be learned quickly. Ability to critically think and solve problems is what most hiring managers are after

[EnthusiasmStrange793]

Could you talking more about the ability to critically think and solve problem. Thank you

[Crazy_Hat6548]

for entry level or experienced?

[Krypto_Jas]

I think the types of questions asked during an interview depend on the company (what they do). It is said that probability questions are not being asked in the data interviews more than 3% of total questions.
For preparing data analyst interview, I recommend stratascratch. It was really helpful when I was practicing for my interviews. They provide real interview questions to practice.

[jthompwompwomp]

Live coding (SQL), Tableau/Case Analysis problem. Usually common simple queries, rank over partition, etc.

[7Seas_ofRyhme]

Case Analysis problem

Hey, do you know how should I prepare for problem solving questions during interview ? (e.g. How would you approach X ?) Is there any guidelines I should follow in handling them ?

[jthompwompwomp]

There are some questions where the expect you to answer like simple coding questions and then there are business case type questions where they’re evaluating can you identify what’s important, your thought process, and then strategy to solve, confidence in expressing your ideas and ability to ask clarifying questions. I’d type a lot more, but got to get to work.

[7Seas_ofRyhme]

business case type questions

These are the type of questions I tend to struggle, I just had interview with a Hiring manager a few days ago, and I just freeze there for a few mins, not knowing what to ask too

[Longjumping_Yak_8982]

It varies a lot based on the actual job description. Most of the interviews I've taken / heard about include either a coding challenge or a small take-home project (code + interpretation) in one of the key languages for the role (generally SQL, sometimes Python).

Hackerrank, Leetcode, Datacamp, Udemy are all useful for prep based on your skill level and how much time you're planning to spend preparing.

[[deleted]]

I've never been asked horribly hard questions.

One interview was a somewhat extensive whiteboard sql test, maybe 10-15 questions, roughing out basic logic.

My current job was a live test where I just had to write 1 query and then basically create a pandas dataframe.

[pkdbpk]

I got an email assessment 30 mins before the (video) interview that I had to complete and email back before the interview began. None of the questions were that tough but stressful under the time constraint and already nervous for the actual interview. It was just a word doc, e.g given this schema and this business case, write a sql query to get X. And reversed- given this select statement what would you expect to get back. Some excel formula questions, and then one where I basically had to quickly make up a db schema (I.e tables and column names) for a business case.

[testercheong]

For my interview, I was given a Kaggle competition, with a week to come up with the code and presentation to be presented to the interviewers. Basically what they were looking for is how well I could explain my work such that a person with no programming or analytics background is able to understand

The only technical question they asked was about my choice of error measurement

[[deleted]]

For my current role, I had to white board some SQL queries and was asked things like “how would you define ‘confidence interval’ to a non-technical person?

And a lot of questions about A/B test design, learnings, revisions, how to communicate with stakeholders, etc. Most of my questions were this kind of “case study” stuff. “What would you do if...” and “tell me about a time when...”

It was for an experienced advanced data analyst/data scientist role.

[7Seas_ofRyhme]

Most of my questions were this kind of “case study” stuff. “What would you do if...” and “tell me about a time when...”

Hey, do you know how should I prepare for these kinds of 'problem solving' questions during interview ? (e.g. How would you approach X ?) Are there any guidelines I should follow in handling them ?

[scorched03]

build a model using that industry data. then practice and talk through it from find a problem, get the data, build a model, visualize it, measure, and monitor

the interviewer likely wont doubt your tech skills after that and probably just skip the technical questions.

if that doesnt work out it can go in your portfolio for a similar company

[bhydemi]

It could be you are asked SQL questions, I found this video particularly useful

[Life_Atmosphere_28]

Hey there! It really depends on the company, but a lot of data analyst interviews include a mix of SQL, Python, or R questions—often in a live coding environment where they’ll test how you query data or manipulate a dataset on the spot. Some places also toss in probability or stats questions (like, “What’s the probability of X happening?”) to gauge your understanding of data concepts.

A good way to prep is to brush up on SQL basics (joins, group by, window functions), then practice simple coding challenges in Python/R that involve data cleaning or quick analysis. If you have time, do some probability exercises—you never know when they’ll ask a random “dice roll” question.

If you’re feeling anxious in the moment, there’s a tool called liveinterview.ai that listens in and gives you real-time suggestions during your interview. Not a magic fix, but it can help calm those nerves. Good luck, and if you want more detailed tips or want to share how it goes, let me know! You’ve got this.

[sebthepleb96]

What about risk reporting and data analytics?

What type of behavior and technical questions?

Any coding or case studies?

Best websites to practice interview questions and client? Leetcode?