LeetCode #182 DuplicateEmails. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,그래프,Graph,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접, 데이터베이스, sql, query, 쿼리
Runtime: 175 ms, faster than 93.09% of MySQL online submissions for Duplicate Emails.
Memory Usage: 0B, less than 100.00% of MySQL online submissions for Duplicate Emails.
LeetCode #182
Q.
SQL Schema
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 |
+----+---------+
Person 테이블에서 중복되는 이메일들을 찾는 SQL 쿼리문을 작성해라
For example, your query should return the following for the above table:
예렬들면, 위의 테이블에서 네 쿼리는 다음과 같이 리턴되어야 한다.
+---------+
| Email |
+---------+
| a@b.com |
+---------+
Note: All emails are in lowercase.
Process
// Process
//1. SELECT Email attribute,
//2. FROM Person table,
//3. In Email GROUP
//4. Check whole Count is over 1
// 처리과정
//1. Email 속성을 찾는데,
//2. Person 테이블에서,
//3. Email 그룹을 짓고
//4. 전체 카운트가 1 이상인 것을 찾는다.
Code.. lemme see example code!!!
코드.. 예제코드를 보자!!!
SELECT Email FROM Person
GROUP BY Email
HAVING Count(*) > 1;
Something else you might like...?
2019/08/14 - [Life/Item review] - Mi Band 4 review, 미밴드4 후기, 장점, 단점, 리뷰, 한글, global review, 미밴드4 글로벌 후기, 리뷰, 구매, 사용방법, setting, 세팅, ProsNCons
2019/08/27 - [Programming] - 개발자 선배들에게서 배운 것들. Things I Learnt from a Senior Software Engineer. 코딩 잘하는 방법, how to code well, 소프트웨어,프로그래머,programmer
2019/09/17 - [Algorithm/Leet Code] - LeetCode #841 KeysAndRooms. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,그래프,Graph,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접
2019/08/28 - [Algorithm/Leet Code] - LeetCode #821 ShortestDistanceToACharacter. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접..
2019/08/25 - [Algorithm/Leet Code] - LeetCode #191 NumberOf1Bits. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,연결리스트
2019/08/19 - [Algorithm/Leet Code] - LeetCode #942 DI StringMatch. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,연결리스트
2019/07/21 - [Algorithm/Leet Code] - LeetCode #590 N-aryTreePostorderTraversal. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,..
2019/07/20 - [Algorithm/Leet Code] - LeetCode #589 N-aryTreePreorderTraversal. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,..
2019/07/17 - [Algorithm/Leet Code] - LeetCode #905 SortArrayByParity. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,연결리..
2019/07/13 - [Algorithm/Leet Code] - LeetCode #994 RottingOranges. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,연결리스트
2019/06/25 - [Algorithm/Leet Code] - LeetCode #766 ToeplitzMatrix. Algorithm,알고리즘,LeetCode,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive,datastructure,techinterview,coding,코딩인터뷰,기술면접,연결리스트
2019/04/14 - [Programming/C++] - C++ Math - sqrt (square root, 제곱근, 루트). stl, math.h, 씨쁠쁠, example code, 예제코드
2018/10/19 - [Programming/Design Pattern ] - Design pattern - Prototype (디자인패턴 - 프로토타입) / Java C++ C#
2019/01/12 - [Algorithm/Code Fights (Code Signal)] - Aracade Intro #60 sudoku. Algorithm,알고리즘,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive
2019/01/12 - [Algorithm/Code Fights (Code Signal)] - Aracade Intro #59 spiralNumbers. Algorithm,알고리즘,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive
2019/01/08 - [Algorithm/Code Fights (Code Signal)] - Aracade Intro #58 messageFromBinaryCode. Algorithm,알고리즘,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive
2019/01/07 - [Algorithm/Code Fights (Code Signal)] - Aracade Intro #57 fileNaming. Algorithm,알고리즘,Codefights,CodeSignal,코드파이트,코드시그널,예제,문제해결능력,example,c++,java,재귀,recursive
2018/12/28 - [Programming/Software Architecture] - Perfecting OO's Small Classes and Short Methods. 완벽한 객체지향의 작은 클래스와 짧은 메소드, Book:ThoughtWorks Anthology, Java,cpp,자바,oop,좋은코드,객체지향프로그래밍 - (#9, Tell, Don't Ask)
2018/12/26 - [Programming/Software Architecture] - Perfecting OO's Small Classes and Short Methods. 완벽한 객체지향의 작은 클래스와 짧은 메소드, Book:ThoughtWorks Anthology, Java,cpp,자바,oop,좋은코드,객체지향프로그래밍 (1)
2019/01/14 - [Programming/Java] - 자바 메모리 누수 체크/확인/고치는 방법, Memory leak check/fix in Java application, cleanCode/좋은코드/oop/객체지향
2019/02/19 - [Life/Health care] - Lysine 라이신 usage/side effects/dosage 효과/효능/부작용/성인,소아 용법, 복용법
2019/02/16 - [Life/Health care] - Finasteride 피나스테라이드,탈모약 usage/side effects/dosage 효능/부작용/효과/sexual effect/두타스테라이드/프로페시아/propecia/finpecia/카피약/copy drug/hair loss
2019/02/25 - [Life/Health care] - Folic Acid 엽산 vitaminB9,비타민M usage/side effects/dosage 효과/효능/부작용/성인,소아 용법, 복용법
2019/02/28 - [Life/Health care] - Vitamin K, 비타민 K usage/side effects/dosage 효능/부작용/성인,소아 용법
2019/03/03 - [Life/Health care] - Vitamin B1, Thiamine, 비타민 B1, 티아민 usage/side effects/dosage 효능/부작용/성인,소아 용법