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Inventory Leak

Mission brief

Challenge Briefing

Hard

Window Functions
SUM() OVER
CTEs

An e-commerce site sold more items than it had in stock. Identify the order_id where the cumulative_sum of sales exceeded the initial_stock for that SKU.

Inventory Leak

Identify the order_id where cumulative sales exceeded initial stock.

The Narrative

An e-commerce site sold more items than it had in stock. Identify the order_id where the cumulative_sum of sales exceeded the initial_stock for that SKU.

Schema Diagram

inventory

skuVARCHAR

initial_stockINT

orders

idINT

skuVARCHAR

quantityINT

order_timeDATETIME

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

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