使用 YEAR(), MONTH(), DAY() 来获取年月日
SELECT YEAR(application_date) as years, count(1) FROM patent GROUP BY YEAR(application_date) ORDER BY years -- YEAR(application_date) 获取年份 -- MONTH(application_date) 获取月份 -- DAY(application_date) 获取日
使用 date_format(application_date, '%Y'),可自定义日期格式
SELECT date_format(application_date, "%Y") as year, count(1) FROM patent GROUP BY date_format(application_date, "%Y")