Note

START TRANSACTION; # 트랜잭션 시작 SELECT * FROM TABLE; # 초기 상태 # 데이터 수정 INSERT INTO, DELETE SELECT * FROM TABLE; # 수정 상태 COMMIT # 수정상태 적용 SELECT * FROM TABLE; # 수정 후 테이블

SELECT * FROM Table WHERE id IN ( SELECT id FROM (SELECT id FROM Table GROUP BY column1,column2 HAVING count(*) > 1) temp_table ) # Table : 테이블 이름 # column1,2 : 테이블 내 겹치는 칼럼

How to compute the min-by-max for each row for a numpy array 2d? # Input np.random.seed(100) a = np.random.randint(1,10, [5,3]) a # Solution np.apply_along_axis(lambda x: np.min(x)/np.max(x), arr=a, axis=1) # output array([ 0.44444444, 0.125 , 0.5 , 1. , 0.11111111])

How to reverse the rows of a dataframe? # Input df = pd.DataFrame(np.arange(25).reshape(5, -1)) # 1 df.iloc[::-1, :] # 2 print(df.loc[df.index[::-1], :]) # output 0 1 2 3 4 4 20 21 22 23 24 3 15 16 17 18 19 2 10 11 12 13 14 1 5 6 7 8 9 0 0 1 2 3 4

How to find the maximum value in each row of a numpy array 2d? # Input np.random.seed(100) a = np.random.randint(1,10, [5,3]) a # 1 np.amax(a, axis=1) # 2 np.apply_along_axis(np.max, arr=a, axis=1) # output array([9, 8, 6, 3, 9])