爲了從2個表

Question

得到與標記學生的頂部三個名字從Oracle數據庫中2代表各科目

假設我有兩個表：
1）學員姓名和卷號
2）表與卷號，主題和標記。

我想要得到的輸出，它會顯示每個學科名稱前3名的學生。

表的腳本，可用於爲：

CREATE TABLE STUDENT (ROLL_NO INT PRIMARY KEY, NAME VARCHAR(20)); 
INSERT INTO STUDENT VALUES (1,'NIKHIL'); 
INSERT INTO STUDENT VALUES (2,'VARUN'); 
INSERT INTO STUDENT VALUES (3,'NISHANT'); 
INSERT INTO STUDENT VALUES (4,'VISHAL'); 
INSERT INTO STUDENT VALUES (5,'GOURAV'); 
INSERT INTO STUDENT VALUES (6,'HEMANT'); 
INSERT INTO STUDENT VALUES (7,'SHUBHAM'); 
INSERT INTO STUDENT VALUES (8,'DHAWAN'); 
INSERT INTO STUDENT VALUES (9,'GAUTAM'); 


CREATE TABLE MARKS (ROLL_NO INT, SUBJECT VARCHAR(20), MARKS INT); 
INSERT INTO MARKS VALUES('1','MATHS','92'); 
INSERT INTO MARKS VALUES('1','SCIENCE','80'); 
INSERT INTO MARKS VALUES('1','ENGLISH','98'); 
INSERT INTO MARKS VALUES('1','HINDI','81'); 
INSERT INTO MARKS VALUES('2','MATHS','89'); 
INSERT INTO MARKS VALUES('2','SCIENCE','100'); 
INSERT INTO MARKS VALUES('2','ENGLISH','81'); 
INSERT INTO MARKS VALUES('2','HINDI','82'); 
INSERT INTO MARKS VALUES('3','MATHS','98'); 
INSERT INTO MARKS VALUES('3','SCIENCE','92'); 
INSERT INTO MARKS VALUES('3','ENGLISH','88'); 
INSERT INTO MARKS VALUES('3','HINDI','83'); 
INSERT INTO MARKS VALUES('4','MATHS','88'); 
INSERT INTO MARKS VALUES('4','SCIENCE','82'); 
INSERT INTO MARKS VALUES('4','ENGLISH','85'); 
INSERT INTO MARKS VALUES('4','HINDI','97'); 
INSERT INTO MARKS VALUES('5','MATHS','94'); 
INSERT INTO MARKS VALUES('5','SCIENCE','90'); 
INSERT INTO MARKS VALUES('5','ENGLISH','97'); 
INSERT INTO MARKS VALUES('5','HINDI','89'); 
INSERT INTO MARKS VALUES('6','MATHS','89'); 
INSERT INTO MARKS VALUES('6','SCIENCE','82'); 
INSERT INTO MARKS VALUES('6','ENGLISH','84'); 
INSERT INTO MARKS VALUES('6','HINDI','85'); 
INSERT INTO MARKS VALUES('7','MATHS','82'); 
INSERT INTO MARKS VALUES('7','SCIENCE','100'); 
INSERT INTO MARKS VALUES('7','ENGLISH','92'); 
INSERT INTO MARKS VALUES('7','HINDI','98'); 
INSERT INTO MARKS VALUES('8','MATHS','99'); 
INSERT INTO MARKS VALUES('8','SCIENCE','91'); 
INSERT INTO MARKS VALUES('8','ENGLISH','86'); 
INSERT INTO MARKS VALUES('8','HINDI','82'); 
INSERT INTO MARKS VALUES('9','MATHS','100'); 
INSERT INTO MARKS VALUES('9','SCIENCE','95'); 
INSERT INTO MARKS VALUES('9','ENGLISH','81'); 
INSERT INTO MARKS VALUES('9','HINDI','81'); 

Run It Here

預先感謝幫助 我需要在Oracle上運行它

Answer 1

下面將加入表，並決定基於標記的排名並通過主題劃分它們

SELECT * 
FROM 
    (SELECT name, 
     subject, 
     marks, 
     row_number() over (partition BY subject order by marks DESC) rank 
    FROM student 
    JOIN marks 
    ON student.roll_no = marks.roll_no 
    ) 
WHERE rank <= 3