{ "data": { "question": { "questionId": "1161", "questionFrontendId": "1075", "boundTopicId": null, "title": "Project Employees I", "titleSlug": "project-employees-i", "content": "
Table: Project
\n+-------------+---------+\n| Column Name | Type |\n+-------------+---------+\n| project_id | int |\n| employee_id | int |\n+-------------+---------+\n(project_id, employee_id) is the primary key of this table.\nemployee_id is a foreign key to Employee
table.\nEach row of this table indicates that the employee with employee_id is working on the project with project_id.\n
\n\n\n\n
Table: Employee
\n+------------------+---------+\n| Column Name | Type |\n+------------------+---------+\n| employee_id | int |\n| name | varchar |\n| experience_years | int |\n+------------------+---------+\nemployee_id is the primary key of this table. It's guaranteed that experience_years is not NULL.\nEach row of this table contains information about one employee.\n\n\n
\n\n
Write an SQL query that reports the average experience years of all the employees for each project, rounded to 2 digits.
\n\nReturn the result table in any order.
\n\nThe query result format is in the following example.
\n\n\n
Example 1:
\n\n\nInput: \nProject table:\n+-------------+-------------+\n| project_id | employee_id |\n+-------------+-------------+\n| 1 | 1 |\n| 1 | 2 |\n| 1 | 3 |\n| 2 | 1 |\n| 2 | 4 |\n+-------------+-------------+\nEmployee table:\n+-------------+--------+------------------+\n| employee_id | name | experience_years |\n+-------------+--------+------------------+\n| 1 | Khaled | 3 |\n| 2 | Ali | 2 |\n| 3 | John | 1 |\n| 4 | Doe | 2 |\n+-------------+--------+------------------+\nOutput: \n+-------------+---------------+\n| project_id | average_years |\n+-------------+---------------+\n| 1 | 2.00 |\n| 2 | 2.50 |\n+-------------+---------------+\nExplanation: The average experience years for the first project is (3 + 2 + 1) / 3 = 2.00 and for the second project is (3 + 2) / 2 = 2.50\n\n", "translatedTitle": null, "translatedContent": null, "isPaidOnly": false, "difficulty": "Easy", "likes": 444, "dislikes": 112, "isLiked": null, "similarQuestions": "[{\"title\": \"Project Employees II\", 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