# Use ARRAY_JOIN to convert each event's tags array into a comma-separated string

Canonical URL: <https://datadriven.io/problems/use-arrayjoin-to-convert-each-events-tags-array-into-a-com-3e7dfd6e>

Domain: SQL · Difficulty: medium

## Problem

Use ARRAY_JOIN to convert each event's tags array into a comma-separated string. Return event_id and the result.

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