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📊 Data & Analytics

These interviews test whether you can turn a vague business question into a specific analysis, whether your SQL is solid, and whether you can explain a finding to someone non-technical. Case-style questions are common even for junior roles.

Common interview questions

Not exact questions you'll be asked — but the shape of what gets asked, and how a strong answer is structured.

Walk me through how you'd investigate a sudden drop in metric X.

Structure beats speed here: check if it's a data/tracking issue first (easy to overlook), segment by time/platform/geography to isolate where the drop is concentrated, then form 2-3 hypotheses and say how you'd test each one.

Write a query to find the second-highest salary in a table.

Mention at least two approaches: a subquery with MAX() excluding the top value, or DENSE_RANK()/ROW_NUMBER() with a window function. Window functions are the more 'senior' answer — use them if comfortable, but a correct subquery is a fine fallback.

How do you handle missing data?

Don't jump straight to 'fill with the mean.' First ask why it's missing (random vs. systematic) — that changes the right approach: drop, impute, or treat 'missing' as its own meaningful category.

Explain a time your analysis changed a decision.

Pick a story with a concrete before/after, even from a class project or personal analysis if you lack work experience — the key is showing the chain from data to insight to action.

How would you explain a p-value to a non-technical manager?

Avoid the textbook definition. Something like: 'it's how likely we'd see a result this strong just by chance, if there was actually no real effect — low means the effect is probably real.' Simple and correct beats precise and confusing.

Your learning path

In order — each step builds on the last.

  1. 01

    SQL joins and window functions cold

    INNER/LEFT/RIGHT joins, GROUP BY with HAVING, and at least RANK()/ROW_NUMBER() — these cover the large majority of SQL screening questions.

  2. 02

    One end-to-end analysis project

    A single project where you pulled real data, cleaned it, found something non-obvious, and visualized it is worth more than five tutorial notebooks.

  3. 03

    Practice explaining stats simply

    Be able to explain p-value, correlation vs. causation, and sample size in one plain sentence each — interviewers often test for this specifically.

4-week study roadmap

A week-by-week plan, not just a topic list. Check items off as you go — your progress is saved on this device.

Week 1

SQL fundamentals

0/3 done
Week 2

One real analysis project

0/3 done
Week 3

Statistics & case practice

0/3 done
Week 4

Storytelling & mock interviews

0/3 done

Before you walk in: field checklist

The field-specific things worth double-checking you've covered.

0/5 done

Interview-day checklist

The same basics matter whatever role you're interviewing for.

0/6 done

Free resources to study from

Cold mail tips for this field

  • —Reference a specific metric or public report from their company if one exists — shows real homework.
  • —Attach or link one chart from your own analysis work, not just a resume.
  • —Ask a genuine question about their data stack — it signals real interest over a template.

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