Need help to count the values in column A if sum of column B equals 0 group by column A.

SELECT    
A, SUM(B) --???   
FROM table  
WHERE DATE = 'yyyy-mm-dd'   
AND B = 0  
GROUP BY A 

>Solution :

A number of A’s which sum(B)=0.

select count(*) countA
from (
    SELECT A
    FROM table  
    WHERE DATE = ... -- your date here
    GROUP BY A 
    HAVING SUM(B)=0
) t