1783. Grand Slam Titles
Table: Players
+----------------+---------+
| Column Name | Type |
+----------------+---------+
| player_id | int |
| player_name | varchar |
+----------------+---------+
player_id is the primary key for this table.
Each row in this table contains the name and the ID of a tennis player.
Table: Championships
+---------------+---------+
| Column Name | Type |
+---------------+---------+
| year | int |
| Wimbledon | int |
| Fr_open | int |
| US_open | int |
| Au_open | int |
+---------------+---------+
year is the primary key for this table.
Each row of this table containts the IDs of the players who won one each tennis tournament of the grand slam.
Write an SQL query to report the number of grand slam tournaments won by each player. Do not include the players who did not win any tournament.
Return the result table in any order.
The query result format is in the following example:
Players table:
+-----------+-------------+
| player_id | player_name |
+-----------+-------------+
| 1 | Nadal |
| 2 | Federer |
| 3 | Novak |
+-----------+-------------+
Championships table:
+------+-----------+---------+---------+---------+
| year | Wimbledon | Fr_open | US_open | Au_open |
+------+-----------+---------+---------+---------+
| 2018 | 1 | 1 | 1 | 1 |
| 2019 | 1 | 1 | 2 | 2 |
| 2020 | 2 | 1 | 2 | 2 |
+------+-----------+---------+---------+---------+
Result table:
+-----------+-------------+-------------------+
| player_id | player_name | grand_slams_count |
+-----------+-------------+-------------------+
| 2 | Federer | 5 |
| 1 | Nadal | 7 |
+-----------+-------------+-------------------+
Player 1 (Nadal) won 7 titles: Wimbledon (2018, 2019), Fr_open (2018, 2019, 2020), US_open (2018), and Au_open (2018).
Player 2 (Federer) won 5 titles: Wimbledon (2020), US_open (2019, 2020), and Au_open (2019, 2020).
Player 3 (Novak) did not win anything, we did not include them in the result table.
with cte as (
select player_id,count(player_id) cnt from (
select wimbledon as player_id from Championships
union all
select Fr_open as player_id from Championships
union all
select US_open as player_id from Championships
union all
select Au_open as player_id from Championships) tbl group by player_id)
select p.player_id, p.player_name, cnt as grand_slams_count from cte c join players p on c.player_id = p.player_id;