# From event_data, return event_id and JSON_EXTRACT_SCALAR(payload, '$.currency') AS currency for even

Canonical URL: <https://datadriven.io/problems/from-eventdata-return-eventid-and-jsonextractscalarpay-484d5d2e>

Domain: SQL · Difficulty: medium

## Problem

From event_data, return event_id and JSON_EXTRACT_SCALAR(payload, '$.currency') AS currency for event_type = 'purchase'. Group by currency and count events per currency as events_for_currency. Exclude rows where currency IS NULL. Order by events_for_currency DESC, currency.

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