LeeHyunjoo

550. Game Play Analysis IV Write a solution to report the fraction of players that logged in again on the day after the day they first logged in, rounded to 2 decimal places. In other words, you need to count the number of players that logged in for at least two consecutive days starting from their first login date, then divide that number by the total number of players. Table: Activity+--------..

585. Investments in 2016 Write a solution to report the sum of all total investment values in 2016 tiv_2016, for all policyholders who: have the same tiv_2015 value as one or more other policyholders, andare not located in the same city as any other policyholder (i.e., the (lat, lon) attribute pairs must be unique).Round tiv_2016 to two decimal places. Table: Insurance+-------------+-------+| C..

197. Rising Temperature Write a solution to find all dates' id with higher temperatures compared to its previous dates (yesterday). Return the result table in any order. Table: Weather+---------------+---------+| Column Name | Type |+---------------+---------+| id | int || recordDate | date || temperature | int |+---------------+---------+ Input: Weather table:+-..

1158. Market Analysis I Write a solution to find for each user, the join date and the number of orders they made as a buyer in 2019. Return the result table in any order. The result format is in the following example. Table: Users+----------------+---------+| Column Name | Type |+----------------+---------+| user_id | int || join_date | date || favorite_brand | varchar |..

1084. Sales Analysis III Write a solution to report the products that were only sold in the first quarter of 2019. That is, between 2019-01-01 and 2019-03-31 inclusive. Return the result table in any order. Table: Product+--------------+---------+| Column Name | Type |+--------------+---------+| product_id | int || product_name | varchar || unit_price | int |+--------------+-----..

SQL 코딩 테스트에서 주로 사용되며 문법이 거의 동일하게 작동하는 MySQL과 SQLite를 기준으로 문법 정리해보기! 1. SQL 기본 구조 및 실행 순서(1) SQL 작성 순서SQL 쿼리는 일반적으로 아래와 같은 순서로 작성되며 select, from 을 제외한 함수의 사용은 선택적이다. SELECT 컬럼명FROM 테이블명[WHERE 조건][GROUP BY 컬럼][HAVING 조건][ORDER BY 컬럼 ASC|DESC][LIMIT 숫자](2) SQL 실제 실행 순서 (Logical Processing Order)SQL 엔진은 위와 같은 작성 순서로 쿼리를 실행하지 않고 아래와 같은 내부 처리 순서가 있다.순서절설명1FROM데이터가 위치한 테이블 또는 서브쿼리에서 시작2ON(JOIN이 있다면) 조..