Grand Slam Titles
<p>Table: <code>Players</code></p>

<pre>
+----------------+---------+
| Column Name    | Type    |
+----------------+---------+
| player_id      | int     |
| player_name    | varchar |
+----------------+---------+
player_id is the primary key (column with unique values) for this table.
Each row in this table contains the name and the ID of a tennis player.
</pre>

<p>&nbsp;</p>

<p>Table: <code>Championships</code></p>

<pre>
+---------------+---------+
| Column Name   | Type    |
+---------------+---------+
| year          | int     |
| Wimbledon     | int     |
| Fr_open       | int     |
| US_open       | int     |
| Au_open       | int     |
+---------------+---------+
year is the primary key (column with unique values) for this table.
Each row of this table contains the IDs of the players who won one each tennis tournament of the grand slam.
</pre>

<p>&nbsp;</p>

<p>Write a solution to report the number of grand slam tournaments won by each player. Do not include the players who did not win any tournament.</p>

<p>Return the result table in <strong>any order</strong>.</p>

<p>The result format is in the following example.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> 
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       |
+------+-----------+---------+---------+---------+
<strong>Output:</strong> 
+-----------+-------------+-------------------+
| player_id | player_name | grand_slams_count |
+-----------+-------------+-------------------+
| 2         | Federer     | 5                 |
| 1         | Nadal       | 7                 |
+-----------+-------------+-------------------+
<strong>Explanation:</strong> 
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.
</pre>
Database
# Write your MySQL query statement below
WITH
    T AS (
        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
    )
SELECT player_id, player_name, COUNT(1) AS grand_slams_count
FROM
    T
    JOIN Players USING (player_id)
GROUP BY 1;
