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SQL • LESSON 134

LOWER

How can we normalize email addresses to lowercase?

Advanced3 Minutes1470 XP
🤔 THE QUESTION

How can we normalize email addresses to lowercase?

💡 WHAT IS IT?

LOWER() converts string characters to lowercase for canonical storage and matching.

🎯 WHAT IS IT USED FOR?

Normalizing email logins, case-insensitive joins, URL slug generation.

💻 EXAMPLE
SELECT LOWER(email) AS normalized_email
FROM employees;

🎯 Mission Objectives

Practice typing production-grade SQL code for LOWER.

  • LOWER() function
  • Email normalization
  • Case-insensitive matching
  • Data standardization