Code reviewMediumcr-g637

Subject Sql index usageLevel Mid–Senior~20 minCommon in Databases & SQL interviewsIndustries Software development

Question

Review this SQL query that powers a daily-signups report over a 40M-row table.

There is a btree index on `users(created_at)` and one on `users(email)`.

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Code to reviewsql

1SELECT user_id, email2FROM users3WHERE DATE(created_at) = '2026-06-20'4  AND LOWER(email) LIKE '%@acme.com'5ORDER BY created_at DESC;

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