Table: Project
+-------------+---------+
| Column Name | Type |
+-------------+---------+
| project_id | int |
| employee_id | int |
+-------------+---------+
(project_id, employee_id) is the primary key of this table.
employee_id is a foreign key to Employee
table.
Each row of this table indicates that the employee with employee_id is working on the project with project_id.
Table: Employee
+------------------+---------+ | Column Name | Type | +------------------+---------+ | employee_id | int | | name | varchar | | experience_years | int | +------------------+---------+ employee_id is the primary key of this table. Each row of this table contains information about one employee.
Write an SQL query that reports all the projects that have the most employees.
Return the result table in any order.
The query result format is in the following example.
Example 1:
Input: Project table: +-------------+-------------+ | project_id | employee_id | +-------------+-------------+ | 1 | 1 | | 1 | 2 | | 1 | 3 | | 2 | 1 | | 2 | 4 | +-------------+-------------+ Employee table: +-------------+--------+------------------+ | employee_id | name | experience_years | +-------------+--------+------------------+ | 1 | Khaled | 3 | | 2 | Ali | 2 | | 3 | John | 1 | | 4 | Doe | 2 | +-------------+--------+------------------+ Output: +-------------+ | project_id | +-------------+ | 1 | +-------------+ Explanation: The first project has 3 employees while the second one has 2.
# Write your MySQL query statement below
SELECT project_id
FROM Project p
GROUP BY project_id
HAVING COUNT(employee_id) >= all(
SELECT COUNT(employee_id)
FROM Project
GROUP BY project_id )
# Write your MySQL query statement below
SELECT project_id
FROM
(
SELECT
project_id,
dense_rank() OVER (ORDER BY COUNT(employee_id) DESC) AS rk
FROM Project
GROUP BY project_id
) AS t
WHERE rk = 1;