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Cleaning Data for Dashboard Tables

MediumSQL & Data Manipulation00:00
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The question is on your right: Cleaning Data for Dashboard Tables. Take a moment with it first.

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Problem

Explain your SQL-first process for turning messy source data into a clean dataset that can power a reliable ABC Education dashboard. Focus on how you inspect data quality, define the target grain, standardize categories and dates, join lookup tables safely, and validate the final output before it reaches a visualization layer.

What This Tests

  • Data wrangling in SQL
  • Choosing the correct grain for reporting
  • Using joins without duplicating rows
  • Structuring transformations with CTEs
  • Standardizing messy values with CASE WHEN and date functions