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How to Be a Top-Notch Data Analyst / Module 10

The analyst's operating system

Four lessons, about 45 minutes. The last module before the capstone — how you run yourself as an analyst once the honeymoon of "new hire learning everything" is over.

Module 10 worksheets A documentation template, a request-intake and triage log, a portfolio case-study skeleton, and an interview prep sheet — the four operational tools this module builds. One .docx, five pages.
Lesson 10.111 minutes

Documenting work so future-you can rerun it in five minutes

Three months from now, Chidi asks you to rerun an analysis you did in your second week. If the only record of how you built it lives in your memory, you're rebuilding it from scratch. A short doc per real piece of analysis — what question it answered, where the data came from, what cleaning decisions you made, and where the final file lives — turns that rebuild into a five-minute task.

The habit isn't documenting everything exhaustively. It's documenting the handful of things you'd genuinely be annoyed to have forgotten.

Keep this
  • Write a short doc for any analysis worth being able to rerun — the question, the source, the key decisions, where it lives.
  • Document selectively, for what you'd actually regret forgetting, not exhaustively for everything.
Lesson 10.211 minutes

A request queue that does not drown you

Once branch managers realise you exist, requests arrive faster than you can process them one at a time in your head. A simple queue — request, requester, scope agreed (per module 1.4), status, deadline — is the difference between a manageable job and a job that quietly runs your evenings.

The minimum viable queue
Columns that matterWhat was asked, scope actually agreed, who asked, when it's due, current status.
The discipline it enablesWhen a fifth urgent request lands, the queue lets you show — not just claim — that four other genuinely urgent things are already ahead of it, and negotiate honestly about order.
Keep this
  • Track every request in one place with its agreed scope and status — memory alone doesn't scale past a handful of concurrent asks.
  • A visible queue turns "everything is urgent" arguments into an honest, shared conversation about order.
Lesson 10.311 minutes

Building a portfolio that survives thirty seconds of attention

A recruiter or hiring manager gives a portfolio roughly thirty seconds before deciding whether to look closer. A dump of every SQL query you've ever written fails this test completely. Three real case studies, each following problem → approach → decision it actually changed, pass it.

What survives thirty seconds

A one-paragraph case study: "Sahara Mart's nine branches reported sales inconsistently, making week-over-week comparisons unreliable. I built a Power Query pipeline that standardised every branch's export automatically, then a Power BI dashboard replacing a fragmented WhatsApp-thread reporting process. Branch managers now check one number instead of arguing about nine different ones every Monday."

Notice the shape: a real problem, a real approach, and a real, specific consequence — not "I learned SQL and Power BI," which says nothing about judgement or impact.

Keep this
  • Three focused case studies (problem → approach → consequence) beat an exhaustive list of every skill or query you've written.
  • State the actual consequence — what changed because of the work — not just the tools used.
Lesson 10.412 minutes

The analyst interview: take-homes, case questions, and what they are testing

An analyst take-home assignment is rarely testing whether you can write correct SQL in isolation — it's testing the whole course's worth of judgement, compressed into two hours: did you profile the data first, did you catch an obvious data quality problem, did you state your assumptions, did you communicate the finding clearly.

What a strong take-home actually demonstrates
  • A short note on data quality issues found and how you handled each — module 4's discipline, on display.
  • Queries that are readable, not just correct — module 3.6's CTE habit.
  • A one-sentence finding stated clearly before the supporting detail — module 9.1's habit.
  • Explicit statement of what you're confident about versus not — module 9.4's habit.

A take-home that's technically correct but skips all four of these looks like someone who can execute instructions. One that includes them looks like someone who can be handed an ambiguous problem and trusted with it — which is the actual job.

Keep this
  • A take-home tests the whole course's judgement, not isolated technical correctness — show your data-quality and communication discipline, not just working code.
  • Explicitly naming your assumptions and confidence level is itself part of what's being evaluated.
Before the drill

Pick a real piece of work from earlier in this course — a drill, an analysis, anything with a genuine before-and-after.

Module 10 drillabout 60 minutes

Write up a case study, under 400 words

Pick your strongest piece of work from modules 1–9 — the fan-out join catch in module 3, the nine-problem cleanup in module 4, the dashboard from module 6, or another. Write it up as a portfolio case study, in under 400 words, following lesson 10.3's structure: problem, approach, decision it actually changed or would change.

What this drill is really testing

Whether you can compress real, technically detailed work into something a non-technical reader would actually finish reading and come away impressed by — which is precisely the compression module 9's whole discipline has been building toward, applied to your own work instead of a hypothetical finding.

Before the capstone

You now have all ten modules' disciplines. The capstone drops you into a new client's genuinely messy week and asks whether they hold up together, under real pressure, without a lesson telling you which one applies.