SQL/LeetCode

문제Table: Tree+-------------+------+| Column Name | Type |+-------------+------+| id | int || p_id | int |+-------------+------+id is the column with unique values for this table. Each row of this table contains information about the id of a node and the id of its parent node in a tree. The given structure is always a valid tree.   Each node in the tree can be one of three types..

문제Table: Activity+--------------+---------+| Column Name | Type |+--------------+---------+| player_id | int || device_id | int || event_date | date || games_played | int |+--------------+---------+(player_id, event_date) is the primary key of this table. This table shows the activity of players of some game. Each row is a record of a player who logged in and played a ..

문제Table: RequestAccepted+----------------+---------+| Column Name | Type |+----------------+---------+| requester_id | int || accepter_id | int || accept_date | date |+----------------+---------+(requester_id, accepter_id) is the primary key (combination of columns with unique values) for this table. This table contains the ID of the user who sent the request, the ID of ..

문제Table: Insurance+-------------+-------+| Column Name | Type |+-------------+-------+| pid | int || tiv_2015 | float || tiv_2016 | float || lat | float || lon | float |+-------------+-------+pid is the primary key (column with unique values) for this table. Each row of this table contains information about one policy where: pid is the policyholder's policy ID. t..

문제Table: Employee+-------------+---------+| Column Name | Type |+-------------+---------+| id | int || name | varchar || department | varchar || managerId | int |+-------------+---------+id is the primary key (column with unique values) for this table. Each row of this table indicates the name of an employee, their department, and the id of their manager. If manager..

문제Table: Activity+--------------+---------+| Column Name | Type |+--------------+---------+| player_id | int || device_id | int || event_date | date || games_played | int |+--------------+---------+(player_id, event_date) is the primary key (combination of columns with unique values) of this table. This table shows the activity of players of some games. Each row is a r..

문제 Table: Scores +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | score | decimal | +-------------+---------+ id is the primary key (column with unique values) for this table. Each row of this table contains the score of a game. Score is a floating point value with two decimal places. Write a solution to find the rank of the scores. The ranking should be ..

문제 Table: Employee +-------------+------+ | Column Name | Type | +-------------+------+ | id | int | | salary | int | +-------------+------+ id is the primary key (column with unique values) for this table. Each row of this table contains information about the salary of an employee. Write a solution to find the nth highest salary from the Employee table. If there is no nth highest salary, return..

문제 Table: Teacher +-------------+------+ | Column Name | Type | +-------------+------+ | teacher_id | int | | subject_id | int | | dept_id | int | +-------------+------+ (subject_id, dept_id) is the primary key (combinations of columns with unique values) of this table. Each row in this table indicates that the teacher with teacher_id teaches the subject subject_id in the department dept_id. Wri..

문제 Table: Employees +-------------+----------+ | Column Name | Type | +-------------+----------+ | employee_id | int | | name | varchar | | manager_id | int | | salary | int | +-------------+----------+ In SQL, employee_id is the primary key for this table. This table contains information about the employees, their salary, and the ID of their manager. Some employees do not have a manager (manage..