All roadmaps
Data analyst
Data analyst path
Query data with SQL, then clean and summarise it with Python and Pandas, and finish with real business questions.
- about 14 weeks at an hour a day
- 6 stages, 54 steps
Read and summarise tables with SQL
about 3 weeks · 13 stepsAfter this stage: You can answer 'how many' and 'how much' questions with a query.
- SQL: tables, rows and columnsLessonFreeHow data is laid out.01
- SQL NULL handlingLessonLockedMissing values change every result.02
- SQL aggregations and groupingLessonLockedTotals and averages per group.03
- SQL multi-table joinsLessonLockedBring related tables together.04
- SQL CASE expressionsLessonLockedLabel and bucket values in a query.05
- SQL window functionsLessonLockedRankings and running totals.06
- SQL 50 practice sheetPracticePractise the queries.07
- Subqueries and CTEsLessonLockedBreak a business question into readable steps.08
- Cleaning text and dates in SQLLessonLockedFix messy values before you count them.09
- Set operationsLessonLockedCombine and compare result sets.10
- Pivoting and unpivotingLessonLockedTurn rows into the columns a report needs.11
- Advanced aggregationsLessonLockedSubtotals and grouping sets.12
- Advanced analytics patternsLessonLockedFunnels, retention and gaps.13
Clean and reshape with Pandas
about 3 weeks · 18 stepsAfter this stage: You can load a messy file, fix it and summarise it in Python.
- Your first Python programLessonFreeEnough Python to drive Pandas.14
- What is pandas?LessonFreeTables in Python.15
- Reading CSV, Excel and JSONLessonFreeGet data in.16
- Cleaning and type castingLessonLockedFix the data before you analyse it.17
- Filtering and slicingLessonLockedPick the rows and columns you need.18
- Grouping and aggregationsLessonLockedThe Pandas twin of GROUP BY.19
- Pandas versus SQLLessonLockedThe same question in both tools.20
- Pandas 30 practice sheetPracticePractise the table work.21
- Variables, types and type hintsLessonLockedThe Python you need before pandas.22
- Lists, dictionaries and setsLessonLockedContainers you will use around every DataFrame.23
- Series and DataFramesLessonFreeThe two objects everything is built on.24
- apply and mapLessonLockedRun your own logic on a column.25
- Transformations and derived columnsLessonLockedAdd the columns your analysis needs.26
- Combining datasetsLessonLockedmerge, join and concat.27
- Reshaping and pivot tablesLessonLockedWide to long and back.28
- Time series in pandasLessonLockedDates, resampling and rolling windows.29
- The .str accessorLessonLockedClean text columns quickly.30
- Advanced groupbyLessonLockedtransform, filter and custom aggregates.31
Think and check like an analyst
about 2 weeks · 9 stepsAfter this stage: You can pin down a vague question, check that your numbers hold up and compare groups fairly.
- From a business question to a table questionLessonFreeDecide the metric, rows and dates first.32
- Your first look at a datasetLessonFreeFive commands before any analysis.33
- Do two sources agree?LessonLockedReconcile before you report a total.34
- Average, median and why they disagreeLessonLockedPick the right average.35
- Rates, not countsLessonLockedCompare groups of different sizes fairly.36
- Reading a trend without being fooledLessonLockedPartial weeks look like crashes.37
- Outliers: keep, cap or remove?LessonLockedDecide without hiding real signal.38
- Capstone: write the findingLessonLockedTurn a result into a clear statement.39
- Capstone: messy data to analysis-readyLessonLockedClean a real mess in pandas.40
Understand warehouse data
about 2 weeks · 4 stepsAfter this stage: You can read a star schema and pick the right table and measure.
- OLTP vs OLAP mental modelLessonLockedWhy reporting data looks different from app data.41
- Star schema: facts, dimensions, grainLessonLockedFind the table and the grain before you query.42
- Additive, semi-additive and non-additive factsLessonLockedKnow which numbers you can safely sum.43
- Views vs materialized viewsLessonLockedHow dashboards stay fast.44
Business questions end to end
about 3 weeks · 7 stepsAfter this stage: You can ask the next question, check the data and give a recommendation.
- Case study: where does the revenue come from?Case studyDecide what counts, then look by week and by customer.45
- Case study: which payment method loses money?Case studyCheck grain, compare rates and size the loss.46
- Case study: where do shoppers drop off?Case studyA funnel, step by step.47
- Case study: do new members come back?Case studyRetention for a subscription app.48
- Case study: which ad deserves the credit?Case studyAttribution in marketing data.49
- Case study: why do rides get cancelled?Case studyFind the pattern behind a problem.50
- Analytics projectsProjectScorecards, experiments and RFM segmentation.51
Get hired
about 1 week · 3 stepsAfter this stage: You have proof you can do the work and answers ready for the interview.