| user_id | spend_date | platform | amount | | ------- | ---------- | -------- | ------ | | 1 | 2019-07-01 | mobile | 100 | | 1 | 2019-07-01 | desktop | 100 | | 2 | 2019-07-01 | mobile | 100 | | 2 | 2019-07-02 | mobile | 100 | | 3 | 2019-07-01 | desktop | 100 | | 3 | 2019-07-02 | desktop | 100 |