golang mysql 获取一个月多少天，第一天，最后一天

golang 获取月份数据

获取每个月第一天

func MonthDay(monthAt time.Time) (firstDay, lastDay string,totalDays int) {
	firstDay = monthAt.AddDate(0, 0, -monthAt.Day()+1).Format("2006-01-02")
	lastDay = monthAt.AddDate(0, 1, -monthAt.Day()).Format("2006-01-02")
	totalDays = monthAt.AddDate(0, 1, -monthAt.Day()).Day()
	return
}

mysql 获取月份数据

mysql> select curdate(),date_format(curdate(),'%Y-%m-01') as first_day,
	last_day(curdate()) last_day,
	day(last_day(curdate())) total_days;
+------------+------------+------------+------------+
| curdate()  | first_day  | last_day   | total_days |
+------------+------------+------------+------------+
| 2022-09-02 | 2022-09-01 | 2022-09-30 |         30 |
+------------+------------+------------+------------+
1 row in set (0.00 sec)