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Cleaning Inherited Spreadsheet Data

EasySQL & Data Manipulation00:00
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Your question is Cleaning Inherited Spreadsheet Data. Take a moment with it on the right.

Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).

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Problem

Context

You inherit a messy spreadsheet or reporting file with inconsistent formats, blank cells, duplicate rows, and unclear column meanings. Before you can trust it for analysis, you need a quick but disciplined way to assess its quality.

Core question

How do you approach cleaning and validating the file so the final output is reliable? In your answer, explain how you identify obvious data issues, decide what to standardize versus flag for review, and verify that the cleaned data still matches the original totals or counts where appropriate.

Scope guidance

Keep your answer practical and SQL-oriented. Focus on the checks you would run, the kinds of transformations you would apply, and how you would confirm the file is ready for reporting without silently changing the underlying meaning of the data.