String Cleaning Pipeline

How can we remove spaces, trim whitespace, and lowercase emails in one step?

Advanced⏱ 3 Minutes⭐ 1530 XP

🤔 THE QUESTION

How can we remove spaces, trim whitespace, and lowercase emails in one step?

💡 WHAT IS IT?

Nesting string functions (LOWER(TRIM(REPLACE(...)))) creates a multi-step data cleaning pipeline.

🎯 WHAT IS IT USED FOR?

Production ELT text cleansing, email deduplication keys, canonical CRM records.

💻 EXAMPLE

SELECT
LOWER(
    TRIM(
        REPLACE(email, ' ', '')
    )
) AS cleaned_email
FROM employees;

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