Data Analyst

01.1Resume

CoreBeginner3–5 h

A one-page resume you can defend line by line.

What this covers

• One-page format — Reverse-chronological, clean fonts, no photos or tables that confuse parsers.
• Project bullets — Action + what you built + a number (users, speed, accuracy).
• Skills section — Only skills you can answer questions on for two minutes.
• ATS readability — Export a text-based PDF and check it with a parser.
• Working links — GitHub, LinkedIn and a live project link that open.
• Tailoring — Reorder bullets to match the job description.

What to practise

• Run your PDF through a parser test
• Rewrite each bullet as action + result
• Remove any skill you can't explain for 2 minutes

Common questions

• Walk me through your resume.
• Which project here are you most proud of, and why?
• Why is this skill on your resume?

Free resources

• OpenResume — Free ATS-friendly resume builder and parser test (Free)
• Jake's Resume (Overleaf) — The LaTeX resume template most SDE freshers use (Free)
• Resume Worded — Resume and LinkedIn scoring (Free plan)
• Jobscan — Match your resume against a job description (Free plan)

Free courses

• Professional Resume Writing — Alison (Free course)
• Resume, Networking, and Interview Skills — Fullbridge (Free to audit)

01.2Tell me about yourself

CoreBeginner1–2 h

A 60–90 second answer: present, past, why this role.

What this covers

• Present — Who you are now: degree, year, focus.
• Past — One or two proof points: a project, internship or result.
• Future — Why this role and this company next.
• Length — 60–90 seconds; stop before you list everything.
• Delivery — Calm pace and eye contact, not a memorised script.

What to practise

• Write it, then say it out loud 5 times
• Record yourself and cut anything over 90 seconds

Common questions

• Tell me about yourself.
• Why should we hire you?
• Where do you see yourself in a few years?

Free resources

• Google Interview Warmup — Free spoken mock interview that prints your transcript (Free)
• BBC Learning English — Structured free English lessons and podcasts (Free)

Free courses

• English@Work: Basic Job Interview Skills — The Hong Kong Polytechnic University (Free to audit)
• Job Interview Preparation For Tech Professionals — University of Cape Town (Free to audit)

01.3Behavioral & STAR

CoreBeginner3–4 h

Stories about teamwork, conflict and failure, told with STAR.

What this covers

• STAR structure — Situation, task, action, result. Spend most of the time on action.
• Story bank — 6–8 real stories you can reuse across questions.
• Teamwork & conflict — Disagreeing respectfully and what you changed.
• Failure & weakness — A real one, what you learned, what you do now.
• Ownership — Times you took initiative without being asked.
• Common HR questions — Why us, why you, strengths, relocation.

What to practise

• Write 6 stories in STAR form
• Map each story to 2–3 common questions
• Practise one story with a friend

Common questions

• Tell me about a time you failed.
• Describe a conflict in a team and what you did.
• What is your biggest weakness?

Free resources

• Tech Interview Handbook — Free guide to coding and behavioral interviews (Free)
• Google Interview Warmup — Free spoken mock interview that prints your transcript (Free)
• Pramp / Exponent peer mocks — Free peer-to-peer mock interviews (Free plan)

Free courses

• Master Behavioral Interviews (for Software Engineers) — freeCodeCamp (Free video)
• Behavioral Interview Practice for Computer Science Students — CodeSignal (Free to audit)
• Soft Skills For Tech Professionals — University of Cape Town (Free to audit)

02.1Statistics & probability

CoreIntermediate10–15 h

The statistics data interviews commonly test, explained in plain words.

What this covers

• Descriptive statistics — Mean, median, variance, percentiles.
• Probability — Conditional probability and Bayes' rule.
• Distributions — Normal, binomial, Poisson and when they apply.
• Sampling & CLT — Why sample means behave predictably.
• Hypothesis testing — p-values, confidence intervals, errors.
• Correlation vs causation — Confounders and how to argue carefully.

What to practise

• Explain a p-value to a non-technical friend
• Solve 20 probability questions

Common questions

• What is a p-value?
• Difference between correlation and causation?
• When would you use the median instead of the mean?

Free resources

• Khan Academy: Statistics and probability — Free statistics course with practice (Free)
• StatQuest — Statistics and ML explained clearly, in videos (Free)
• Khan Academy — Maths and science from scratch (Free)

Free courses

• Descriptive statistics | Probability and Statistics | Khan Academy — Khan Academy (Free video)
• Inferential statistics | Probability and Statistics | Khan Academy — Khan Academy (Free video)
• Random variables and probability distributions | Probability and Statistics | Khan Academy — Khan Academy (Free video)

02.2Excel for analysis

CoreBeginner6–10 h

The spreadsheet skills many analyst roles test live.

What this covers

• Formulas — IF, SUMIFS, COUNTIFS, text and date functions.
• Lookups — XLOOKUP, INDEX-MATCH, VLOOKUP limits.
• Pivot tables — Summaries, filters, calculated fields.
• Charts — Choosing the right chart, clean formatting.
• Cleaning data — Duplicates, text to columns, trimming.
• Speed — Shortcuts and tidy layouts.

What to practise

• Analyse a public dataset with pivots and charts
• Rebuild one report using XLOOKUP and SUMIFS

Common questions

• How does VLOOKUP differ from XLOOKUP?
• How would you find duplicates in a column?

Free resources

• Excel Easy — Free Excel tutorial from basics to pivot tables (Free)
• Excel help and learning — Microsoft's own Excel training videos (Free)
• Khan Academy — Maths and science from scratch (Free)

Free courses

• Excel for Beginners — Great Learning (Free course)
• Excel for Intermediate Level — Great Learning (Free course)
• VLOOKUP in Excel — Great Learning (Free course)

03.1SQL for analytics

CoreIntermediate10–15 h

Business questions answered in SQL, from joins to window functions.

What this covers

• Joins & filters — Inner, left, anti-joins and their traps.
• Aggregation — GROUP BY, HAVING, conditional sums.
• Window functions — RANK, LAG, running totals, moving averages.
• CTEs & subqueries — Breaking hard questions into steps.
• Dates — Grouping by week or month, cohorts.
• NULLs & duplicates — Handling messy data correctly.

What to practise

• Solve 30 interview-style SQL questions
• Write a monthly retention query from scratch

Common questions

• Find the second-highest salary per department.
• Calculate 7-day rolling average sales.
• Difference between WHERE and HAVING?

Free resources

• Mode SQL tutorial — SQL for analysis, from basics to window functions (Free)
• DataLemur — SQL and analytics interview questions (Free plan)
• StrataScratch — Real SQL and Python data interview questions (Free plan)
• SQLZoo — SQL by doing, in the browser (Free)

Free courses

• SQL and Relational Databases 101 — IBM (Free course)
• CS50's Introduction to Databases with SQL — Harvard University (Free video)

03.2Data cleaning & wrangling

CoreIntermediate6–10 h

Getting messy data ready, the part of the job that takes most time.

What this covers

• Missing values — Drop, fill or flag, and why.
• Outliers — Spotting them and deciding what to do.
• Types & formats — Dates, currencies, categories.
• Joining datasets — Keys, duplicates, row explosions.
• Reproducibility — Scripted steps instead of manual edits.

What to practise

• Clean a messy public dataset and document every step
• Find three data-quality issues in a sample file

Common questions

• How do you handle missing values?
• How would you check a dataset is correct?

Free resources

• Kaggle Learn — Short practical courses: Python, Pandas, ML, SQL (Free)
• Excel Easy — Free Excel tutorial from basics to pivot tables (Free)
• StrataScratch — Real SQL and Python data interview questions (Free plan)

Free courses

• Data Cleaning — Kaggle (Free course)
• Sensor Data Cleaning: Filter Techniques — Alison (Free course)
• Basics of Python Data Wrangling — Great Learning (Free course)

03.3Data visualisation & dashboards

CoreIntermediate6–10 h

Choosing the right chart and building dashboards people use.

What this covers

• Chart choice — Bars, lines, scatter and when each works.
• Dashboard design — Key numbers first, filters, clear titles.
• A BI tool deeply — Power BI or Tableau: models, measures, filters.
• Storytelling — Insight, evidence, recommendation.
• Avoiding misleading charts — Axes, scales and colour.

What to practise

• Build and publish one dashboard on a public dataset
• Turn one chart into a 3-sentence insight

Common questions

• How would you design a sales dashboard?
• When is a pie chart a bad idea?

Free resources

• Tableau Public — Free Tableau to build and publish dashboards (Free)
• Power BI on Microsoft Learn — Free Power BI learning paths (Free)
• Excel Easy — Free Excel tutorial from basics to pivot tables (Free)

Free courses

• Data Visualization with Python — IBM (Free course)
• Data Visualization with R — IBM (Free course)
• Data Visualization — Kaggle (Free course)

04.1Business metrics

CoreIntermediate4–8 h

KPIs, funnels and retention: the language of analytics interviews.

What this covers

• KPIs — Revenue, conversion, active users, churn.
• Funnels — Step-by-step conversion and drop-offs.
• Retention & cohorts — Who comes back and when.
• Unit economics — CAC, LTV, margins.
• North-star metrics — One metric that reflects value delivered.

What to practise

• Define 5 KPIs for an app you use
• Build a cohort retention table from sample data

Common questions

• What metrics would you track for a food delivery app?
• Daily active users dropped 10%. What do you check?

Free resources

• Exponent — Product, data and engineering interview questions and guides (Free plan)
• StrataScratch — Real SQL and Python data interview questions (Free plan)
• Mode SQL tutorial — SQL for analysis, from basics to window functions (Free)

Free courses

• Mastering 11 Essential Business KPIs — Alison (Free course)
• Top Five KPIs for Small Businesses — Alison (Free course)

04.2Analytics case questions

CoreIntermediate6–10 h

Structured answers to "metric dropped" and "should we launch" questions.

What this covers

• Clarify the question — Definitions, time frame, segments.
• Hypotheses — Internal vs external causes, data issues first.
• Segmenting — Platform, region, new vs returning.
• Sizing & estimates — Back-of-envelope numbers.
• Recommendation — A clear answer with next steps.

What to practise

• Solve five metric-drop cases aloud
• Practise one estimation question a day

Common questions

• Orders fell 15% last week. How do you investigate?
• How would you measure the success of a new feature?

Free resources

• Exponent — Product, data and engineering interview questions and guides (Free plan)
• DataLemur — SQL and analytics interview questions (Free plan)
• PrepLounge — Case partners and practice cases (Free plan)

Free courses

• Optimization Methods in Business Analytics — MITx (Free course)
• Business Analytics & Text Mining Modeling Using Python — IIT Roorkee (Free course)
• Business Analytics & Data Mining Modeling Using R Part II — IIT Roorkee (Free course)

05.1Data portfolio projects

CoreIntermediate10–20 h

Two or three projects that show how you think with data.

What this covers

• Pick real questions — A question someone would pay to answer.
• Show the process — Data source, cleaning, analysis, limits.
• Clear write-up — Summary first, charts second, code last.
• Public links — GitHub, Kaggle or a dashboard link.
• Defending choices — Be ready for "why this method?"

What to practise

• Finish one end-to-end project with a written summary
• Present a project in 5 minutes to a friend

Common questions

• Walk me through a project you are proud of.
• What would you do with more time or data?

Free resources

• Kaggle Learn — Short practical courses: Python, Pandas, ML, SQL (Free)
• GitHub — Where your projects live (Free)
• Tableau Public — Free Tableau to build and publish dashboards (Free)

Free courses

• Data Analysis Projects — Great Learning (Free course)
• Exploratory Data Analysis Projects — Great Learning (Free course)
• Python Projects for Data Analysis — Great Learning (Free course)

05.2Mock interviews

CoreBeginner3–5 h

At least two full practice interviews before the real one.

What this covers

• Realistic setting — Same format, time limit and dress as the real round.
• Common questions first — Introduction, motivation, experience, weaknesses.
• Feedback — Ask what was unclear or too long.
• Recording — Watch yourself once; fix fillers and pace.
• Role questions — Add 3–5 questions specific to your field.

What to practise

• Do two mock interviews with a friend or senior
• Use a spoken practice tool and read the transcript

Common questions

• Tell me about yourself.
• Why this role?

Free resources

• Google Interview Warmup — Free spoken mock interview that prints your transcript (Free)
• Pramp / Exponent peer mocks — Free peer-to-peer mock interviews (Free plan)
• Tech Interview Handbook — Free guide to coding and behavioral interviews (Free)

Free courses

• Software Engineering Job Interview – Full Mock Interview — freeCodeCamp (Free video)

06.1Company research

CoreBeginner1–2 h

The product, the role, the job description and recent news.

What this covers

• The business — What it sells and to whom.
• The role — What the job description really asks for.
• Recent news — Launches, results, announcements.
• Interview format — The rounds, if the company shares them.
• Your fit — Three reasons, matched to the job description.

What to practise

• Write 3 reasons you want this role
• Match 3 JD lines to your experience

Common questions

• Why do you want to work here?
• What do you know about our product?

Free resources

• GeeksforGeeks — Company-wise questions and theory (Free plan)
• Tech Interview Handbook — Free guide to coding and behavioral interviews (Free)

06.3Final checklist

CoreBeginner30 min

Logistics, documents, setup and a calm night before.

What this covers

• Logistics — Time, timezone, link or address.
• Documents — Resume copies, ID, certificates if asked.
• Tech check — Camera, mic, internet, charger.
• Night before — Sleep, light revision, no new topics.

What to practise

• Do a 5-minute tech check the day before
• Lay out documents and clothes the night before

Free resources

• Google Interview Warmup — Free spoken mock interview that prints your transcript (Free)