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Investigate Reporting Count Discrepancies

MediumSQL · PostgreSQL00:00
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Your question is Investigate Reporting Count Discrepancies. Start with the requirements and the three tables on the right.

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Problem

Compare Alabama Staffing reporting snapshot counts against database-derived confirmed placement counts by client and day for January 2024. Return both totals, the discrepancy, and a status that highlights matches, mismatches, and rows missing from one side.

Schema

Tables
  • clients
  • placements
  • reporting_snapshots

What This Tests

  • Joining aggregated reporting data to source-of-truth data
  • Using CTEs to separate metric definitions
  • Handling NULLs and missing rows correctly
  • Classifying discrepancies with CASE
Tablesclientsplacementsreporting_snapshots
Your solutionPostgreSQL
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