我正在进行SQL查询,并且我试图对子查询的结果求和,但没有成功。该命令不会执行 有人能帮助我吗?
我正在做的查询是:
SELECT cm.course_id,cm.course_name, sum (select max(SCORE) from
ATTEMPT where GRADEBOOK_GRADE_PK1 = GG.PK1 group by 1)
FROM gradebook_main gm
JOIN course_main cm ON cm.pk1 = gm.crsmain_pk1
JOIN gradebook_grade gg ON gm.pk1 = gg.gradebook_main_pk1
JOIN course_users cu ON cu.pk1 = gg.course_users_pk1
JOIN users u ON u.pk1 = cu.users_pk1
WHERE U.user_id = '1616894251'
group by cm.course_id, cm.course_name
谢谢!
答案 0 :(得分:0)
我已经尝试将你的subselect构建为连接表..hopre按列分组为GRADEBOOK_GRADE_PK1
SELECT
cm.course_id
, cm.course_name
, sum ( t.max_score
)
FROM gradebook_main gm
JOIN course_main cm ON cm.pk1 = gm.crsmain_pk1
JOIN gradebook_grade gg ON gm.pk1 = gg.gradebook_main_pk1
JOIN course_users cu ON cu.pk1 = gg.course_users_pk1
JOIN users u ON u.pk1 = cu.users_pk1
JOIN (
select GRADEBOOK_GRADE_PK1, max(SCORE) max_score
from ATTEMPT
group by GRADEBOOK_GRADE_PK1
) t on t.GRADEBOOK_GRADE_PK1 = GG.PK1
WHERE U.user_id = '1616894251'
group by cm.course_id, cm.course_name