获取 MySQL 数据库中每月的条目数

Question

我有一个 MySQL 数据库，其中包含两列的预订：

BookingDate (datetime)
Status (varchar with the values of Confirmed, Open, Unconfirmed, Closed, Canceled)

我想统计每个月状态为已关闭、已打开或已确认的条目数。稍后我将使用 PHP 将这些数据导出到图表中，因此我需要将其传递到数组中。

在 MySQL 中执行此操作的最佳方法是什么？我希望结果如下所示：

mm/yy -> # of entires

Answer 1

考虑：

select date_format(booking_date, '%m/%y'), count(*) nb_entries
from mytable
where status in ('Closed', 'Open', 'Confirmed')
group by year(booking_date), month(booking_date), date_format(booking_date, '%m/%y')
order by year(booking_date), month(booking_date)

如果您希望每个状态有一列，那么：

select 
    date_format(booking_date, '%m/%y'), 
    count(*) nb_entries,
    sum(status = 'Closed') nb_entries_closed,
    sum(status = 'Open') nb_entries_open,
    sum(status = 'Confirmed') nb_entries_confirmed
from mytable
where status in ('Closed', 'Open', 'Confirmed')
group by year(booking_date), month(booking_date), date_format(booking_date, '%m/%y')
order by year(booking_date), month(booking_date)

Answer 2

SELECT DATE_FORMAT(booking_date, '%m/%y') `month and year`, 
       SUM(status IN ('Closed', 'Open', 'Confirmed')) `# of entires`
FROM `booking reservations`
-- WHERE city = 'LA'
GROUP BY DATE_FORMAT(booking_date, '%m/%y')