주댕이의 공부 기록

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com25일차 - 메리 크리스마스 2024: https://solvesql.com/problems/merry-christmas-2024/ https://solvesql.com/problems/merry-christmas-2024/ solvesql.com  # 풀이SELECT 'Merry Christmas!'SELECT 'Merry Christmas!': 'Merry Christmas!' 문자열을 반환한다.

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com24일차 - 세 명이 서로 친구인 관계 찾기:https://solvesql.com/problems/friend-group-of-3/ https://solvesql.com/problems/friend-group-of-3/ solvesql.com  # 풀이SELECT DISTINCT e1.user_a_id AS user_a_id, e1.user_b_id AS user_b_id, e2.user_b_id AS user_c_idFROM ed..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com23일차 - 유량(Flow)와 저량(Stock):https://solvesql.com/problems/flow-and-stock/ https://solvesql.com/problems/flow-and-stock/ solvesql.com  # 풀이WITH acquisition_data AS ( SELECT strftime ('%Y', acquisition_date) AS acquisition_year, COUNT(*..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com22일차 - 친구 수 집계하기: https://solvesql.com/problems/number-of-friends/ https://solvesql.com/problems/number-of-friends/ solvesql.com # 풀이WITH normalized_edges AS ( SELECT CASE WHEN user_a_id normalized_edges CTESELECTCASE WHEN user_a_i..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com21일차 - 세션 유지 시간을 10분으로 재정의하기: https://solvesql.com/problems/redefine-session-2/ https://solvesql.com/problems/redefine-session-2/ solvesql.com  # 풀이WITH user_events AS ( SELECT user_pseudo_id, event_timestamp_kst, event_name, ..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com20일차 - 미세먼지 수치의 계절간 차이: https://solvesql.com/problems/finedust-seasonal-summary/ https://solvesql.com/problems/finedust-seasonal-summary/ solvesql.com  # 풀이WITH seasonal_data AS ( SELECT CASE WHEN measured_at BETWEEN '2022-03-01' A..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com19일차 - 전국 카페 주소 데이터 정제하기:https://solvesql.com/problems/refine-cafe-address/ https://solvesql.com/problems/refine-cafe-address/ solvesql.com  # 풀이SELECT TRIM(SUBSTR(address, 1, INSTR(address, ' ') - 1)) AS sido, TRIM( SUBSTR( address, ..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com18일차 - 펭귄 날개와 몸무게의 상관 계수:https://solvesql.com/problems/correlation-penguin/ https://solvesql.com/problems/correlation-penguin/ solvesql.com  # 풀이SELECT species, ROUND( ( COUNT(*) * SUM(flipper_length_mm * body_mass_g) - SUM(flipper_lengt..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com17일차 - 멀티 플랫폼 게임 찾기:https://solvesql.com/problems/multiplatform-games/ https://solvesql.com/problems/multiplatform-games/ solvesql.com  # 풀이-- 2012년 이후 출시된 게임WITH after_2012 AS (SELECT g.name AS game_name, p.name AS platform_nameFROM games gJOIN..

# 링크solvesql Advent of SQL 2024: https://solvesql.com/collections/advent-of-sql-2024/ https://solvesql.com/collections/advent-of-sql-2024/ solvesql.com16일차 - 스테디셀러 작가 찾기: https://solvesql.com/problems/find-steadyseller-writers/ https://solvesql.com/problems/find-steadyseller-writers/ solvesql.com  # 풀이WITH fictions AS ( SELECT DISTINCT author, year FROM books WHERE genre = 'Fiction'),co..