HAZEL

New Companies >> 문제 Amber's conglomerate corporation just acquired some new companies. Each of the companies follows this hierarchy: Given the table schemas below, write a query to print the company_code, founder name, total number of lead managers, total number of senior managers, total number of managers, and total number of employees. Order your output by ascending company_code. Note: The tab..

1] Japan Population >> 문제 Query the sum of the populations for all Japanese cities in CITY. The COUNTRYCODE for Japan is JPN. Input Format The CITY table is described as follows: >> 문제해결 코드 SELECT SUM(POPULATION) from CITY WHERE COUNTRYCODE = 'JPN' www.hackerrank.com/challenges/japan-population/problem Japan Population | HackerRank Query to the sum of the populations of all Japanese cities in CI..

1] 182. Duplicate Emails >> 문제 Write a SQL query to find all duplicate emails in a table named Person. +----+---------+ | Id | Email | +----+---------+ | 1 | a@b.com | | 2 | c@d.com | | 3 | a@b.com | +----+---------+ For example, your query should return the following for the above table: +---------+ | Email | +---------+ | a@b.com | +---------+ >> 문제 해결 코드 select Email from person group by Emai..

1] 595. Big Countries >> 문제 There is a table World +-----------------+------------+------------+--------------+---------------+ | name | continent | area | population | gdp | +-----------------+------------+------------+--------------+---------------+ | Afghanistan | Asia | 652230 | 25500100 | 20343000 | | Albania | Europe | 28748 | 2831741 | 12960000 | | Algeria | Africa | 2381741 | 37100000 | ..