Welcome to Subscribe On Youtube
Formatted question description: https://leetcode.ca/all/1693.html
1693. Daily Leads and Partners
Level
Easy
Description
Table: DailySales
+-------------+---------+
| Column Name | Type |
+-------------+---------+
| date_id | date |
| make_name | varchar |
| lead_id | int |
| partner_id | int |
+-------------+---------+
This table does not have a primary key.
This table contains the date and the name of the product sold and the IDs of the lead and partner it was sold to.
The name consists of only lowercase English letters.
Write an SQL query that will, for each date_id and make_name, return the number of distinct lead_id’s and distinct partner_id’s.
Return the result table in any order.
The query result format is in the following example:
DailySales table:
+-----------+-----------+---------+------------+
| date_id | make_name | lead_id | partner_id |
+-----------+-----------+---------+------------+
| 2020-12-8 | toyota | 0 | 1 |
| 2020-12-8 | toyota | 1 | 0 |
| 2020-12-8 | toyota | 1 | 2 |
| 2020-12-7 | toyota | 0 | 2 |
| 2020-12-7 | toyota | 0 | 1 |
| 2020-12-8 | honda | 1 | 2 |
| 2020-12-8 | honda | 2 | 1 |
| 2020-12-7 | honda | 0 | 1 |
| 2020-12-7 | honda | 1 | 2 |
| 2020-12-7 | honda | 2 | 1 |
+-----------+-----------+---------+------------+
Result table:
+-----------+-----------+--------------+-----------------+
| date_id | make_name | unique_leads | unique_partners |
+-----------+-----------+--------------+-----------------+
| 2020-12-8 | toyota | 2 | 3 |
| 2020-12-7 | toyota | 1 | 2 |
| 2020-12-8 | honda | 2 | 2 |
| 2020-12-7 | honda | 3 | 2 |
+-----------+-----------+--------------+-----------------+
For 2020-12-8, toyota gets leads = [0, 1] and partners = [0, 1, 2] while honda gets leads = [1, 2] and partners = [1, 2].
For 2020-12-7, toyota gets leads = [0] and partners = [1, 2] while honda gets leads = [0, 1, 2] and partners = [1, 2].
Solution
Use count(distinct) to obtain the number of distinct lead_id’s and distinct partner_id’s for each date_id and make_name. Then use group by date_id, make_name so that the results are obtained by each (date_id, make_name) pair.
# Write your MySQL query statement below
select date_id, make_name, count(distinct lead_id) as unique_leads, count(distinct partner_id) as unique_partners
from DailySales
group by date_id, make_name;