MYSQL 添加行的列值

Question

我有一个学生table作为

的问题

+-------------+-------------+-------------+-------------+---------------+
| roll_number | name        | subject_one | subject_two | subject_three |
+-------------+-------------+-------------+-------------+---------------+
|           1 |  Sheila     |          32 |          48 |            64 |
|           2 | Rachel      |          24 |          21 |            25 |
|           3 | Christopher |          55 |          12 |            10 |
+-------------+-------------+-------------+-------------+---------------+

我想要将输出打印为

+-------------+-------------+-------------+
| roll_number | name        | total       | 
+-------------+-------------+-------------+
|           1 |  Sheila     |          144|
|           2 | Rachel      |          70 |     
|           3 | Christopher |          77 |
+-------------+-------------+-------------+

和 select 所有学生的分数都大于 75 ?? 我如何使用 MYSQL 实现此目的 ??

Answer 1

我认为您只需要 aggregate functions 并使用它们就足够了。不知道能不能帮到你。

SELECT roll_number , name , (subject_one + subject_two + subject_three) AS total FROM STUDENT HAVING total > 75 ;