Next-Day SMS Confirmation

SQLEasyJunior levelTikTok~15 min

Problem

**[Asked at TikTok]**

New TikTok accounts receive an SMS verification code. The growth team wants to find
users who confirmed their account **exactly one day after** signing up (not the same
day, not two or more days later).

Return a list of `user_id` values, ordered ascending.

Tables

Example rows — the live problem includes the full dataset.

signups

signup_id	user_id	signup_date

confirmations

conf_id	user_id	status	conf_date

Expected output

Your answer should return 2 rows with the columns user_id.

Starter code (SQL)

SELECT *
FROM signups;

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Solution & explanation

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