Dataset pack

App event log

Raw app events, several per user per day, with hand-typed user IDs and a few broken dates.

Fictional data · UTF-8 CSV, every value quoted so padding and leading zeros survive; empty fields are missing values · free for personal and classroom practice · practise it in Count distinct users per day.

events 23 rows × 3 columns

Download events.csv (Pro)

Data dictionary

event_id: Unique event ID.
day: Event date, YYYY-MM-DD as text.
user_id: User ID as logged; case and padding vary.

Values are shown in quotes so leading and trailing spaces are visible. ∅ means the cell is missing. Exercises are also graded on hidden datasets that are never published.