+---------+------------+------------+-----------------------+-----------------+---------------------+
| exam_id | student_id | subject_id | assignment_mark_total | test_mark_total | exams_mark_obtained |
+---------+------------+------------+-----------------------+-----------------+---------------------+
| 1 | 19 | 1 | 20 | 30 | 50 |
| 1 | 20 | 1 | 18 | 27 | 48 |
| 1 | 21 | 1 | 16 | 27 | 49 |
| 1 | 22 | 1 | 16 | 29 | 47 |
| 1 | 23 | 1 | 0 | 0 | 0 |
| 1 | 24 | 1 | 0 | 0 | 0 |
| 1 | 25 | 1 | 0 | 0 | 0 |
| 1 | 26 | 1 | 0 | 0 | 0 |
| 1 | 27 | 1 | 0 | 0 | 0 |
| 1 | 28 | 1 | 0 | 0 | 0 |
| 1 | 29 | 1 | 0 | 0 | 0 |
| 1 | 30 | 1 | 0 | 0 | 0 |
| 1 | 31 | 1 | 0 | 0 | 0 |
| 1 | 32 | 1 | 0 | 0 | 0 |
| 1 | 33 | 1 | 0 | 0 | 0 |
| 1 | 34 | 1 | 0 | 0 | 0 |
| 1 | 35 | 1 | 0 | 0 | 0 |
| 1 | 36 | 1 | 0 | 0 | 0 |
| 1 | 37 | 1 | 0 | 0 | 0 |
| 1 | 38 | 1 | 0 | 0 | 0 |
| 1 | 39 | 1 | 0 | 0 | 0 |
| 2 | 19 | 1 | 20 | 21 | 49 |
| 2 | 20 | 1 | 20 | 21 | 50 |
| 2 | 21 | 1 | 16 | 27 | 46 |
| 2 | 22 | 1 | 0 | 0 | 0 |
| 2 | 23 | 1 | 0 | 0 | 0 |
| 2 | 24 | 1 | 0 | 0 | 0 |
| 2 | 25 | 1 | 0 | 0 | 0 |
| 2 | 26 | 1 | 0 | 0 | 0 |
| 2 | 27 | 1 | 0 | 0 | 0 |
| 2 | 28 | 1 | 0 | 0 | 0 |
| 2 | 29 | 1 | 0 | 0 | 0 |
| 2 | 30 | 1 | 0 | 0 | 0 |
| 2 | 31 | 1 | 0 | 0 | 0 |
| 2 | 32 | 1 | 0 | 0 | 0 |
| 2 | 33 | 1 | 0 | 0 | 0 |
| 2 | 34 | 1 | 0 | 0 | 0 |
| 2 | 35 | 1 | 0 | 0 | 0 |
| 2 | 36 | 1 | 0 | 0 | 0 |
| 2 | 37 | 1 | 0 | 0 | 0 |
| 2 | 38 | 1 | 0 | 0 | 0 |
| 2 | 39 | 1 | 0 | 0 | 0 |
| 3 | 19 | 1 | 0 | 27 | 36 |
| 3 | 20 | 1 | 0 | 24 | 41 |
| 3 | 21 | 1 | 0 | 25 | 48 |
| 3 | 22 | 1 | 0 | 0 | 0 |
| 3 | 23 | 1 | 0 | 0 | 0 |
| 3 | 24 | 1 | 0 | 0 | 0 |
| 3 | 25 | 1 | 0 | 0 | 0 |
| 3 | 26 | 1 | 0 | 0 | 0 |
| 3 | 27 | 1 | 0 | 0 | 0 |
| 3 | 28 | 1 | 0 | 0 | 0 |
| 3 | 29 | 1 | 0 | 0 | 0 |
| 3 | 30 | 1 | 0 | 0 | 0 |
| 3 | 31 | 1 | 0 | 0 | 0 |
| 3 | 32 | 1 | 0 | 0 | 0 |
| 3 | 33 | 1 | 0 | 0 | 0 |
| 3 | 34 | 1 | 0 | 0 | 0 |
| 3 | 35 | 1 | 0 | 0 | 0 |
| 3 | 36 | 1 | 0 | 0 | 0 |
| 3 | 37 | 1 | 0 | 0 | 0 |
| 3 | 38 | 1 | 0 | 0 | 0 |
| 3 | 39 | 1 | 0 | 0 | 0 |
+---------+------------+------------+-----------------------+-----------------+---------------------+
63 rows in set (0.00 sec)
您好，我有一个学校报告表的示例数据库，我希望能够获得一个数组结果，其中包含 3 个学期的各个科目的总和
我希望得到这样的结果，即每个科目 (assignment_mark_total + test_mark_total + exams_mark_obtained) AS 分数的总和，其中 exam_id =1&2&3
+--------+
| scores |
+--------+
| 253 |
| 249 |
| 254 |
| 92 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
| 0 |
+--------+
最佳答案
我假设您正在查找每个学生 3 次考试的总分。尝试这个查询:
SELECT
SUM(assignment_mark_total + test_mark_total + exams_mark_obtained) AS scores
FROM
table_name
WHERE
exam_id in (1, 2, 3)
GROUP BY
student_id
您可能还想在所选列列表中添加 student_id。
关于mysql - 对单个 MYSQL 表中的多列求和，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/37458456/