Question

I have a column ‘hour’
I have a column ‘kind’ (it can be 1,2 or 3)

I’d like to do something like:

SELECT count(id), SUM(hour) as totHour, SUM( IF ( kind = 1, 1, 0 ) ) as countKindOne

or

SELECT count(id), SUM(hour) as totHour, COUNT( IF ( kind = 1 ) ) as countKindOne

But mysql tell me I’ve an error… what’s the error!?

Please see this stackoverflow topic: MySQL SUM IF field b = field a

.. I’m not able to reply this …

Answer 1

You can use a CASE statement:

SELECT count(id), 
    SUM(hour) as totHour, 
    SUM(case when kind = 1 then 1 else 0 end) as countKindOne