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Lesson 1

Start Here: Syllabus, Datasets and How This Course Works

The three-week plan, the three datasets, every assignment and project date, and how to set up Power BI Desktop.

Webbo3 Power BI Cohort 1 13 min read Free

Webbo3 Power BI · Cohort 1 · Start Here

Start Here: Syllabus, Datasets and How This Course Works

Three weeks, sixteen days, one business you will know inside out, and two more you will prove yourself on.

By the end of today you can

  • Say who Webbo Oil is, what went wrong, and the five questions your dashboard must answer
  • Say what you will build each week, and when every assignment and project is due
  • Download the Webbo Oil workbook and know what is in each sheet
  • Install Power BI Desktop and set it up the way this course expects
  • Read a lesson: the click paths, the formula boxes and the results you check yourself against

Power BI is the tool a business uses to turn a pile of spreadsheets into one page a manager can read in thirty seconds. This course teaches you to build that page from the pile, properly.

You spend the three weeks on one company, Webbo Oil Stations Ltd. Every day adds a layer: first you get its data in, then you clean it, then you model it, then you measure it, and finally you turn it into a dashboard its Managing Director can use. In Week 3 you prove it twice more: alone on PayLink Nigeria, and with your pod on Jade Hotels & Resorts.

1. The Client: Webbo Oil Stations Ltd

The Company

Webbo Oil Stations Ltd started in 2013 with one filling station in Sabon Gari, Kano. It has since grown to 7 stations across Lagos (Ikeja and Lekki), Abuja, Port Harcourt, Ibadan, Kano and Enugu. It sells petrol, diesel, kerosene, engine oil and grease, and employs around 17 station attendants across all its locations.

The company has never had a proper reporting system. Each station manager keeps a logbook and types up a weekly summary in whatever format they are used to. Someone in Head Office pastes these into one long spreadsheet at month end. Nobody has ever built a dashboard from it.

The Business Problem

In June 2023 the government removed the fuel subsidy. In Webbo Oil's own sales, petrol went from about ₦185 a litre in May 2023 to ₦491 in June, almost overnight, and kept climbing to ₦899 by December 2024. The Managing Director, Alhaji Musa Bello, has a business that looks the same on paper (still 7 stations, still selling fuel), but he has no idea whether it is healthier or weaker than before.

He has also pushed his stations for two years to sell more engine oil and grease alongside fuel, on the theory that a customer already at the pump is an easy upsell. Nobody has ever checked whether that strategy is working.

The Brief, in His Own Words

Alhaji Musa Bello, Managing Director

"I have 7 stations and I still run this business by phone calls and gut feeling. Fuel price has tripled since the subsidy went. I need to know which of my stations are actually making money for me and which ones are dead weight. I need to know if this oil and grease push I've been shouting about for two years did anything at all. And I want a dashboard on my phone, not another spreadsheet nobody opens. Build me something I can actually use to make decisions."

The Five Questions Your Dashboard Must Answer

  1. Which stations bring in the most revenue, and which are falling short of their target?
  2. What happened to sales volume and revenue around the June 2023 price jump? Did people buy less fuel when the price rose, or keep buying the same amount at a higher cost?
  3. Fuel or lubricants: which product line actually carries the business? Was the upsell push worth it?
  4. Do stations differ in how customers pay (cash, POS, transfer), and does that matter for the business?
  5. How does 2024 compare with 2023, station by station and month by month?

Why the Data Looks Like This

The workbook you are given is exactly what Head Office receives. Seven different station managers type these logs, so station names appear in different capitals and spacing. Dates are typed however each manager's phone or computer defaults to, so there are three different date formats in the same column. A few rows are duplicated because a manager submitted the same log twice by mistake. Some attendant names are missing because those pumps run unmanned or self-service.

This Is the Job, Not a Warm-Up

This is not difficulty added to make the course hard. It is what real business data looks like before an analyst touches it. Cleaning it properly is the job, not a warm-up before the job.

Your Deliverable

WhatDetail
Power BI dashboardBuilt from the cleaned, modelled data, covering the five questions above
Short insight write-up3 to 5 key findings, in plain language the Managing Director can act on
PresentationPresented as if Alhaji Musa Bello himself is in the room
Picture This

Picture a Managing Director who has run seven stations on gut feeling for years, opening one page on his phone and finally seeing which ones pay.

2. The Syllabus

Week 1: Getting Data In and Cleaning It

DayWhat you learn
Day 1Power BI Desktop interface. Connecting to data (Get Data, Navigator)
Day 2Power Query Editor overview. Data cleaning in Power Query
Day 3Data transformation in Power Query
Day 4Lab: clean Sales_2023 together, fix mistakes as a class
Day 5Appending and merging queries

Week 2: Modelling and DAX

DayWhat you learn
Day 6Lab: Append and Merge together. Loading data to the model. What is a data model
Day 7Star schema. Creating relationships
Day 8Calculated columns vs measures. DAX basics
Day 9Lab: build relationships in Model view. Write first DAX measures
Day 10CALCULATE

Week 3: Time, Visuals and Delivery

DayWhat you learn
Day 11Lab: CALCULATE together. Solo Project released: PayLink Nigeria
Day 12Time intelligence. Solo Project work continues
Day 13Building visuals
Day 14Solo Project due. Lab: time intelligence and visuals together. Pod Project released: Jade Hotels
Day 15Slicers and drill-through. Dashboard layout and storytelling. Pod work
Day 16Pod presentations

Assignments and Projects

ItemReleasedDueWhat it is
Assignment 1Day 4Day 6Clean Sales_2024 on your own, using the steps built on Sales_2023
Assignment 2Day 9Day 11Build the full Webbo Oil star schema and explain the fact table
Assignment 3Day 13Day 15A one-page Webbo Oil dashboard: KPI card, bar chart, trend line, slicer
Solo ProjectDay 11Day 14PayLink Nigeria: clean, model, measure and dashboard, alone
Pod ProjectDay 14Day 16 (presented)Jade Hotels & Resorts as a team: full pipeline, festive season analysis, channel commission breakdown
Each One Has Its Own Page

Every assignment and project has a lesson of its own in this course, placed straight after the day it is released, with the full brief, the hand-in and how it is marked.

3. The Datasets

Definition

A dataset here is the set of tables that together describe one business. Webbo Oil's arrives as one Excel workbook with a sheet per table.

DatasetThe businessUsed for
Webbo Oil Stations Ltd7 filling stations selling petrol, diesel, kerosene, engine oil and grease, 2023 and 2024Live teaching, all three weeks
PayLink NigeriaA mobile money network of 41 agents in 10 states: deposits, withdrawals, airtime, bills and transfersSolo Project, released Day 11
Jade Hotels & ResortsFive hotels and resorts taking bookings through six channelsPod Project, released Day 14

Download Webbo Oil now. The other two are on their project pages, released on the day the project starts.

Webbo Oil Stations Ltd

Download all as one zip file (webbo-oil-stations.zip)

Save it in a folder you will not move, such as Documents\Webbo3 Power BI\webbo-oil. Power BI remembers the full path to the file, so moving it later breaks your report until you point it at the new place.

What Is in Each Sheet

SheetWhat it holds
CoverA title page: company details and a list of the sheets
Sales_2023Raw daily sales log, all 7 stations, 2023
Sales_2024Raw daily sales log, all 7 stations, 2024
Station_MasterStation names, city and region
Product_MasterProduct list: fuels and lubricants
Attendant_DirectoryStaff list with contact and hire details
Station_TargetsA revenue target per station
What we are looking atWe want to see the first rows of Sales_2023 exactly as the workbook holds them, before anybody has cleaned anything. The dots show spaces that should not be there.
Sales_2023, as it arrives
ABC 123TransactionIDABC 123DateABC 123StationNameABC 123ProductNameABC 123AttendantNameABC 123QuantityABC 123UnitPrice_NGNABC 123TotalAmount_NGNABC 123PaymentMethod
1TXN-2023-0003832023-02-13Bodija·Filling·Station·PMS (PETROL)Amina Nwosu9.7187.41,817.78Cash·
2TXN-2023-00246813/10/2023BODIJA FILLING STATIONEngine OilSegun·Adeyemi·23,402.876,805.74CASH·
3TXN-2023-0021612023-09-10Bodija Filling Stationpms (petrol)bisi chukwu39.7612.6124,320.62POS·
4TXN-2023-0027892023-11-20gra filling stationpms (petrol)KEMI BALOGUN41638.4226,175.22CASH
5TXN-2023-00110305/05/2023Wuse Filling StationPMS (Petrol)Halima·Umeh·36.1179.686,486.45Cash·
6TXN-2023-0011422023-05-09INDEPENDENCE LAYOUT FILLING STATIONGreaseChinwe Chukwu31,202.43,607.2pos
7TXN-2023-00213907/09/2023Bodija Filling StationPMS (PETROL)segun adeyemi44.5629.9328,031.88POS
8TXN-2023-00310127/12/2023···sabon·gari·filling·station·····grease····Ifeanyi·Suleiman··31,215.033,645.09CASH
9 COLUMNS, 3,189 ROWS · first 8 shown

Already you can see the problems this course fixes: names in capitals and with extra spaces, dates written three ways, and empty attendant names. Each one has a lesson.

What we are looking atWe want to see Station_Master, one row per station: the lookup table for station details.
Station_Master
ABCStationIDABCStationNameABCCityABCRegionDATEDateOpened
1STN01Ikeja Filling StationLagosSouth West01/03/2015
2STN02Lekki Filling StationLagosSouth West15/06/2017
3STN03Wuse Filling StationAbujaNorth Central20/01/2016
4STN04GRA Filling StationPort HarcourtSouth South10/09/2014
5STN05Bodija Filling StationIbadanSouth West05/04/2018
6STN06Sabon Gari Filling StationKanoNorth West12/11/2013
7STN07Independence Layout Filling StationEnuguSouth East28/02/2019
5 COLUMNS, 7 ROWS
What we are looking atWe want to see Product_Master, one row per product, and whether it is Fuel or Lubricant.
Product_Master
ABCProductIDABCProductNameABCCategoryABCUnitOfMeasure
1P01PMS (Petrol)FuelLitres
2P02AGO (Diesel)FuelLitres
3P03DPK (Kerosene)FuelLitres
4P04Engine OilLubricantUnits
5P05GreaseLubricantUnits
4 COLUMNS, 5 ROWS
What we are looking atWe want to see Station_Targets, one target per station (Day 5 asks whether it is really monthly).
Station_Targets
ABCStationIDABCStationName1²3MonthlyRevenueTarget_NGN
1STN01Ikeja Filling Station18,000,000
2STN02Lekki Filling Station15,000,000
3STN03Wuse Filling Station14,000,000
4STN04GRA Filling Station20,000,000
5STN05Bodija Filling Station9,000,000
6STN06Sabon Gari Filling Station8,500,000
7STN07Independence Layout Filling Station7,000,000
3 COLUMNS, 7 ROWS
Picture This

Picture seven station managers each keeping their own notebook, in their own handwriting, for two years. Your job is to turn those notebooks into one reliable page.

4. Setting Up Power BI Desktop

Definition

Power BI Desktop is free and runs on Windows only. There is a web version (Power BI Service) for sharing reports, but the cleaning and modelling you learn here happen in Desktop.

Install it

1.Microsoft Store › Search "Power BI Desktop" › Get
2.Open Power BI Desktop › Sign in (optional, close the box) › Blank report
  • Use the Microsoft Store version. It updates itself every month, so your screen matches the class.
  • On a Mac? Power BI Desktop does not run on macOS. Use a Windows laptop, or Windows in Parallels. Tell your tutor on Day 1, not on Day 4.
  • 8 GB of memory is comfortable. It will run on 4 GB, slowly, with nothing else open.

One Setting to Check on Day 1

Some of Webbo Oil's dates are written day first (13/10/2023), the Nigerian and British way. Power BI reads dates with your computer's regional setting, and many laptops are set to the United States, where the month comes first. You will learn to handle this properly on Day 2; for now, check the setting so you know what you have:

Check your locale

1.File › Options and settings › Options › Current File: Regional Settings › Locale for import
Try This

Install Power BI Desktop, open a blank report, and find the Regional Settings page above. Write down what it says. If it says English (United States), you will meet the date problem on Day 2, and that is exactly what we want.

5. How to Read Each Lesson

Every lesson follows the same pattern, so you always know where you are:

  • Definition, then a real-life example, then the types, before anything is clicked or typed.
  • Click paths in grey boxes with a yellow edge: the exact buttons to press, in order. All of Power Query is done this way: you never type code to clean data.
  • Formula boxes in dark editors, from Week 2: the DAX measures you type in the formula bar, with every step commented, and a "What this code does" strip above each one.
  • Result panes underneath: the preview grid, card or chart that the step produces on the workbook.
The Results Are Your Answer Key

Every number in a result pane is calculated from the same workbook you downloaded, using the same steps. If your number is different, you have not found a Power BI bug: one of your steps differs from the lesson. Go back through Applied Steps until the row counts match.

6. How Work Is Handed In

  • Hand-ins are links, not uploads. Save your .pbix file and screenshots to Google Drive, set sharing to "Anyone with the link can view", and paste the link on the assignment.
  • You can edit a hand-in until a tutor marks it.
  • Late work is marked, with the deadline on the page. Missing work is not.
  • Name every file with your name and the task: Chidinma_Okafor_Assignment1.pbix.

Do This Now

  1. Read the brief in section 1 twice, and write the five questions at the top of your notebook.
  2. Install Power BI Desktop from the Microsoft Store.
  3. Download the Webbo Oil workbook into a folder you will not move.
  4. Open it in Excel and find three problems in the Sales_2023 sheet yourself.
  5. Check your locale setting and write it down.
  6. Create a Google Drive folder for your hand-ins.

Tick Before You Move On

  • ☐ I can say what Alhaji Musa Bello wants to know, in my own words
  • ☐ Power BI Desktop opens on my laptop
  • ☐ The Webbo Oil workbook is saved in a folder I will not move
  • ☐ I know when all three assignments and both projects are due
  • ☐ I know my Power BI locale setting

Quick Recap

Webbo Oil has 7 stations, two years of messy sales, and a Managing Director with five questions. Power BI connects, cleans, models and reports, in that order. PayLink Nigeria is your solo proof; Jade Hotels is your team's. Result panes are your answer key: match the row counts and the numbers. Hand-ins are links to Google Drive, editable until marked.

Final Scenario

Three weeks from now, Alhaji Musa Bello opens your dashboard on his phone and asks, "So which of my stations are dead weight, and did the oil and grease push do anything?"

You answer from a page you built from the raw workbook, and you can explain every number on it, down to the step in Power Query that made it right.

That is where this starts. Day 1 is opening the program and getting the data in.

Next, Day 1: the Power BI Desktop interface, and connecting to the Webbo Oil workbook with Get Data and the Navigator.

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