The Referral Cohort
Kindled's referral programme rewards customers who invite friends, and the person running it has to report on who those invitations actually brought in. The report is a plain list of names with the day each person registered, read in arrival order so the programme's momentum over the month is visible. Accounts that arrived through any other channel are not part of this report.
users — one row per person who has created an account. source records how they arrived: organic means they found Kindled themselves, paid_search means they clicked a bought advert, and referral means an existing customer invited them. signup_date is the day they registered.
| id | name | source | signup_date |
|---|---|---|---|
| 1 | Aiden Cole | organic | 2023-05-01 |
| 2 | Bianca Reyes | paid_search | 2023-05-02 |
| 3 | Carlos Mora | organic | 2023-05-03 |
| 4 | Delia Frank | referral | 2023-05-04 |
| 5 | Ewan Blake | paid_search | 2023-05-05 |
| 6 | Fiona Grey | organic | 2023-05-06 |
| 7 | Gus Herrera | referral | 2023-05-07 |
| 8 | Hana Ito | paid_search | 2023-05-08 |
The table already exists in the database — there is nothing to create or load.
Task: Write a query that returns two columns, name and signup_date, for the people whose recorded channel is the referral programme, earliest signup first.
Example output — shape only, on invented people and dates:
| name | signup_date |
|---|---|
| Nadia Petrov | 2022-11-03 |
| Owen Blackwood | 2022-11-21 |
Sign in to solve this problem
Reading problems is free for everyone — solving them (Run, Submit, and tracking what you've solved) needs an account.
Sign in