Checking data before you trust it
Find duplicates, missing values, impossible numbers and orphaned rows in a running club's results before they end up in a leaderboard.
- The skill
- Check a table for duplicates, gaps, impossible values and broken links before you report anything from it.
- You make
- A clean leaderboard for a running club whose results were typed in by volunteers at the finish line.
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Builds on 35 Cleaning messy text. Free to try: SQL Foundations and the playground.
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