pgsql按日, 周, 月, 季度, 年统计数据

代码如下

日: DAY; 周: WEEK; 月: MONTH; 季度: QUARTER; 年: YEAR

	select 
	date_trunc('DAY', create_time) as statisticTime,
	user_name, count(0) 
	from user 
	GROUP BY date_trunc('DAY', create_time), user_name

参考: 
https://www.cnblogs.com/fxust/p/8384707.html