使用INTERVAL的MySQL查询问题，如果没有提供数据则需要0

i have the following statement:

我有以下声明:

SELECT
count(rs.rsc_id) as counter
FROM shots as rs
where rsc_rs_id = 345354
AND YEAR(rs.timestamp) = YEAR(DATE_SUB(CURDATE(), INTERVAL 6 MONTH))
GROUP BY DATE_FORMAT(rs.timestamp,'%Y%m')
SE