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Learn data analysis, one skill at a time.

Step-by-step Excel, Power Query and dashboard tutorials from my live classes, using real Nigerian business data.

Excel sheet showing a VLOOKUP formula on a product lookup table

6 October 2026 · 4 min read

VLOOKUP vs XLOOKUP: Which Should You Use in Excel?

VLOOKUP or XLOOKUP? See the syntax, the 6 key differences and real examples with a Nigerian fintech dataset, so you know exactly which lookup to use in Excel.

  • Excel
  • Lookups
  • Formulas
Joshua explaining Power Query in Power BI Desktop, with captions

4 October 2026 · 5 min read

Clean Data in Excel with Power Query: A Step-by-Step Guide

Clean messy data once and refresh it forever. A beginner's guide to Excel Power Query: remove duplicates, fix blanks, merge tables and load clean data.

  • Excel
  • Power Query
  • Data cleaning