# Normalize all email addresses to lowercase for consistent comparison

Canonical URL: <https://datadriven.io/problems/normalize-all-email-addresses-to-lowercase-for-consistent-co-ad9f0dde>

Domain: SQL · Difficulty: medium

## Problem

Normalize all email addresses to lowercase for consistent comparison. Show username and the lowercased email as normalized_email.

## Related

- [All practice problems](https://datadriven.io/problems)
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