The Skimming Intern

Mission brief

Challenge Briefing

Medium

JOIN
GROUP BY
HAVING
Aggregation

An ambitious intern thought they were slick by recreating a plot from a 90s cult classic—skimming (taking small amounts of money for themselves) from transactions. While it seemed like a foolproof plan, the core ledger doesn't lie. Your job is to audit the system and find every Ledger ID where the recorded total doesn't match the actual sum of its transactions.

The Skimming Intern

Audit the corporate ledger to find tiny transaction discrepancies.

The Narrative

Schema Diagram

ledger

idINT

expected_amountDECIMAL

transactions

idINT

ledger_idINT

amountDECIMAL

Challenge a Friend

One SQL table. One SQL condition.
Still tricky for most developers.

SQL Editor

Terminal Output

Initializing Database Engine v1.8.0...

Write a SQL query, then click Run Query

Keep practicing

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coders.sh *

The Skimming Intern

The Narrative

Schema Diagram

Challenge a Friend

SQL Editor

Terminal Output

Try another challenge