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所有數學課程成績 大於 語文課程成績的學生的學號

所有數學課程成績 大於 語文課程成績的學生的學號

CREATE TABLE course (
id int,
sid int ,
course string,
score int
) ;

// 插入資料
// 欄位解釋:id, 學號, 課程, 成績
INSERT INTO course VALUES (1, 1, 'yuwen', 43);
INSERT INTO course VALUES (2, 1, 'shuxue', 55);
INSERT INTO course VALUES (3, 2, 'yuwen', 77);
INSERT INTO course VALUES (4, 2, 'shuxue', 88);
INSERT INTO course

VALUES (5, 3, 'yuwen', 98);
INSERT INTO course VALUES (6, 3, 'shuxue', 65);

求:所有數學課程成績 大於 語文課程成績的學生的學號

select sid,case when course="yuwen" then score else 0 end as yuwen,
case when course="shuxue" then score else 0 end as shuxue
from course;

1 43 0
1 0 55
2 77 0
2 0 88
3 98 0
3 0 65
select tmp.sid,Max(tmp.yuwen) as yuwen,max(tmp.shuxue) as shuxue
from(
select sid,case when course="yuwen" then score else 0 end as yuwen,
case when course="shuxue" then score else 0 end as shuxue
from course
) tmp
group by tmp.sid;

1 43 55
2 77 88
3 98 65
select stmp.sid
from (
select tmp.sid,Max(tmp.yuwen) as yuwen,max(tmp.shuxue) as shuxue
from(
select sid,case when course="yuwen" then score else 0 end as yuwen,
case when course="shuxue" then score else 0 end as shuxue
from course
) tmp
group by tmp.sid
) stmp where stmp.shuxue > stmp.yuwen;