MySQL随机id受列限制

Question

I have a table with id's ordered from 1 to 300 which have more columns (A,B,C,D,etc)

How to get a random id restricted by the info in column C for example

Example

ID   column C
1    teacher
2    student
3    teacher
4    student
etc...

Imagine i only want id random from "students" in column C (in this example it can only be 2 or 4)

Thanks

Answer 1

Here is one way:

select id
from table t
where c = 'student'
order by rand()
limit 1;

With only 300 rows in the table, the performance should be fine.