Monthly Retained Users
Problem
**[Asked at Facebook/Meta]**
A user is considered **retained** in a given month if they were active in
BOTH that month AND the previous month.
Given a table of user activity logs, count the number of retained users for
each month in 2023. Order by month.
Tables
Example rows — the live problem includes the full dataset.
activity_log
| log_id | user_id | event_type | event_date |
|---|
Expected output
Your answer should return 3 rows with the columns activity_month, retained_users.
Starter code (SQL)
SELECT *
FROM activity_log;Solve this SQL question free
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Solution & explanation
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