Friend Requests I
Meta
Problem Statement
Meta data scientists track user engagement through social interactions. You need to determine the overall acceptance rate of friend requests.
The acceptance rate is calculated as the number of unique accepted requests divided by the total number of unique friend requests sent.
Rules:
- A unique request is defined by the sender_id and send_to_id pair.
- A unique acceptance is defined by the requester_id and accepter_id pair.
- The result should be rounded to 2 decimal places.
- If there are no requests at all, the acceptance rate should be 0.00.
- Output column: accept_rate.
Example logic:
If user 1 sends a request to user 2, and user 1 sends another request to user 2 (duplicate), it only counts as one unique request. The same applies to acceptances.
Tests your understanding of
Counting, Division and Subqueries
Input Tables
Friend_Requests
| sender_id(INTEGER) | send_to_id(INTEGER) | request_date(DATE) |
|---|---|---|
| 1 | 2 | 2026-01-01 |
| 1 | 3 | 2026-01-01 |
| 1 | 4 | 2026-01-01 |
| 2 | 3 | 2026-01-02 |
| 3 | 4 | 2026-01-02 |
| 3 | 4 | 2026-01-03 |
Request_Accepted
| requester_id(INTEGER) | accepter_id(INTEGER) | accept_date(DATE) |
|---|---|---|
| 1 | 2 | 2026-01-02 |
| 1 | 3 | 2026-01-02 |
| 2 | 3 | 2026-01-03 |
| 3 | 4 | 2026-01-04 |
| 3 | 4 | 2026-01-05 |
User_Activity
| user_id(INTEGER) | last_login(TIMESTAMP) |
|---|---|
| 1 | 2026-01-05 10:00:00 |
| 2 | 2026-01-05 11:00:00 |
| 3 | 2026-01-05 12:00:00 |
| 4 | 2026-01-05 13:00:00 |
| 5 | 2026-01-05 14:00:00 |
| 6 | 2026-01-05 15:00:00 |
Expected Output
| accept_rate(DECIMAL) |
|---|
| 0.8 |
Tags
EasyCountingDivisionSubqueries
5-10 min
72%