How to conditionally handle division by zero with MySQL

Question

In MySQL, this query might throw a division by zero error:

SELECT ROUND(noOfBoys / noOfGirls) AS ration
FROM student;

If noOfGirls

Answer 1

Yes, you can do a case:

select case when noOfGirls=0 then noOfBoys 
       else  round(noOfBoys/noOfGirls) end as ration 
from student;

But you probably want:

select case when noOfGirls=0 then 1 
       else  round(noOfBoys/noOfGirls) end as ration 
from student;