ror_coding

문제를 잘 읽자!!! subquery를 잘 활용하자..! Question Write a solution to:Find the name of the user who has rated the greatest number of movies. In case of a tie, return the lexicographically smaller user name.Find the movie name with the highest average rating in February 2020. In case of a tie, return the lexicographically smaller movie name.The result format is in the following example. Code select name a..

20 20이 self join하는 예외 케이스 나눠서 풀기 ! QuestionYou are given a table, Functions, containing two columns: X and Y.Two pairs (X1, Y1) and (X2, Y2) are said to be symmetric pairs if X1 = Y2 and X2 = Y1.Write a query to output all such symmetric pairs in ascending order by the value of X. List the rows such that X1 ≤ Y1.Sample InputSample Output20 2020 2122 23 Point 20 20이 하나만 있을 때 서로 self join해서 20 20 ..