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Basics of Sets and Relations #1 A, B 합집합의 개수? {1,2,3,4,5,6,7,8} => 8 Basics of Sets and Relations #2 A, B 교집합의 개수? {2,3,4,5,6} => 5 Basics of Sets and Relations #3 A, B 차집합의 개수? {1} => 1 Basics of Sets and Relations #4 A x B 카테시안 곱으로 나올 수 있는 총 수는? 6 x 7 = 42 Basics of Sets and Relations #5 σ 는 표준편차라고 한다. σ(Number 2 select count(*) from Student where number < 3000; Basics of Sets and Relations #6..

Julia conducted a 15 days of learning SQL contest. The start date of the contest was March 01, 2016 and the end date was March 15, 2016. Write a query to print total number of unique hackers who made at least 1 submission each day (starting on the first day of the contest), and find the hacker_id and name of the hacker who made maximum number of submissions each day. If more than one such hacker..

MSSQL, MySQL, ORACLE 등의 SQL코드를 붙여넣기 한 후 [Format SQL] 버튼을 클릭하면 코드가 자동으로 정렬된다. https://www.dpriver.com/pp/sqlformat.htm 그리고 아직 사용해보진 않았지만 입력한 SQL을 visualize 해주는 기능이 있다.

Print Prime Numbers SET @i = 2; SET @isPrime = 0; SET @result = ''; DELIMITER $$ CREATE PROCEDURE PrintPrime(IN num INT) BEGIN WHILE @i 1 DO IF @i % @j = 0 THEN SET @isPrime = 0; END IF; SET @j = @j - 1; END WHILE; IF @isPrime = 1 THEN SET @result = CONCAT(@result, @i, '&'); END IF; SET @i = @i + 1; END WHILE ; SET @result = SUBSTR(@result, ..