我想从数据库表中获取过去12个月的记录。以下是我迄今为止尝试过的方法。
SELECT COUNT(s.id), date_part('month', s.viewed_at) month_number
FROM statistics_maps_view as s
INNER JOIN maps as m
ON s.maps_id=m.id Where m.users_id = $users_id group by month_number ORDER BY month_number DESC LIMIT 12
我知道它会按月份对记录进行分组。但是,如果某个月没有记录,是否有一种方法可以添加Count = 0
?