A Beginner's Lessons on ETL, Excel Macros, and Power Query for Data Cleaning

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A data learner shares their experience discovering ETL — the process of extracting, transforming, and loading data — describing it as the foundation of nearly every data project. They initially found Excel macros intimidating but quickly learned these automated scripts could eliminate hours of manual data correction. Exploring Power Query further expanded their toolkit, offering a visual way to connect multiple data sources and reshape messy datasets efficiently. The writer concludes that data cleaning is less about technical skill alone and more about adopting a patient, methodical mindset. Their key takeaway is that clean data is what separates meaningful analysis from unreliable results.

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