HAZEL

>> 문제 You did such a great job helping Julia with her last coding contest challenge that she wants you to work on this one, too! The total score of a hacker is the sum of their maximum scores for all of the challenges. Write a query to print the hacker_id, name, and total score of the hackers ordered by the descending score. If more than one hacker achieved the same total score, then sort the re..

>> 문제 Weather Observation Station 17 Query the Western Longitude (LONG_W)where the smallest Northern Latitude (LAT_N) in STATION is greater than 38.7780. Round your answer to decimal places. -> LONG_W 을 소수점 4자리까지 가져와라. 조건 1, LAT_N이 38.7780 보다 큰 것 조건 2 . 조건 1중에 가장 작은 LAT_N이다. Input Format The STATION table is described as follows: where LAT_N is the northern latitude and LONG_W is the western lon..

Weather Observation Station 5 >> 문제 Query the two cities in STATION with the shortest and longest CITY names, as well as their respective lengths (i.e.: number of characters in the name). If there is more than one smallest or largest city, choose the one that comes first when ordered alphabetically. The STATION table is described as follows: where LAT_N is the northern latitude and LONG_W is the..

Weather Observation Station 7 >> 문제 Query the list of CITY names ending with vowels (a, e, i, o, u) from STATION. Your result cannot contain duplicates. Input Format The STATION table is described as follows: where LAT_N is the northern latitude and LONG_W is the western longitude. >> 기본적으로 푸는 방법 SELECT DISTINCT city FROM station WHERE city LIKE '%a' OR city LIKE '%e' OR city LIKE '%i' OR city L..

Weather Observation Station 6 >> 문제 Query the list of CITY names starting with vowels (i.e., a, e, i, o, or u) from STATION. Your result cannot contain duplicates. Input Format The STATION table is described as follows: where LAT_N is the northern latitude and LONG_W is the western longitude. >> 기본적으로 푸는 방법 select DISTINCT city FROM station WHERE city LIKE 'a%' OR city LIKE 'e%' OR city LIKE 'i%..

180. Consecutive Numbers >> 문제 +-------------+---------+ | Column Name | Type | +-------------+---------+ | id | int | | num | varchar | +-------------+---------+ id is the primary key for this table. Write an SQL query to find all numbers that appear at least three times consecutively. Return the result table in any order. The query result format is in the following example: Logs table: +----+-..

The Report >> 문제 You are given two tables: Students and Grades. Students contains three columns ID, Name and Marks. Grades contains the following data: Ketty gives Eve a task to generate a report containing three columns: Name, Grade and Mark. Ketty doesn't want the NAMES of those students who received a grade lower than 8. The report must be in descending order by grade -- i.e. higher grades ar..

Challenges >> 문제 Julia asked her students to create some coding challenges. Write a query to print the hacker_id, name, and the total number of challenges created by each student. Sort your results by the total number of challenges in descending order. If more than one student created the same number of challenges, then sort the result by hacker_id. If more than one student created the same numb..

184. Department Highest Salary >> 문제 The Employee table holds all employees. Every employee has an Id, a salary, and there is also a column for the department Id. +----+-------+--------+--------------+ | Id | Name | Salary | DepartmentId | +----+-------+--------+--------------+ | 1 | Joe | 70000 | 1 | | 2 | Jim | 90000 | 1 | | 3 | Henry | 80000 | 2 | | 4 | Sam | 60000 | 2 | | 5 | Max | 90000 | 1..

196. Delete Duplicate Emails >> 문제 Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id. +----+------------------+ | Id | Email | +----+------------------+ | 1 | john@example.com | | 2 | bob@example.com | | 3 | john@example.com | +----+------------------+ Id is the primary key column for this table. For example, afte..