Filter Date Ranges with Rolling Intervals in SQL

Question

Given a `user_activity` table, write a query to return all activity logs recorded in the last 30 days (`activity_time >= CURRENT_DATE - INTERVAL '30 days'`). Return `user_id`, `action`, and `activity_time`.

Accepted Answer

Optimal Solution:
SELECT user_id, action, activity_time
FROM user_activity
WHERE activity_time >= CURRENT_TIMESTAMP - INTERVAL '30 days'
ORDER BY activity_time DESC;

Technical Explanation:
Using `CURRENT_TIMESTAMP - INTERVAL '30 days'` makes the query dynamically rolling without hardcoded calendar dates.

log_id	user_id	action	activity_time
1	10	login	2026-08-25 10:00:00
2	10	checkout	2026-06-01 12:00:00