PostgreSQL date_trunc() 和timestamp

timestamp

01.SELECT now()::timestamp + '1 year';

02.SELECT now()::timestamp + '1 month';

03.SELECT now()::timestamp + '1 day';

04.SELECT now()::timestamp + '1 hour';

05.SELECT now()::timestamp + '1 min';

06.SELECT now()::timestamp + '1 sec';

07.select now()::timestamp + '1 year 1 month 1 day 1 hour 1 min 1 sec';

08.SELECT now()::timestamp + (col || ' day')::interval FROM table

date_trunc()

select date_trunc('month',now()) +interval '12 h';
//每月1号 12点
select date_trunc('month',now()) + interval '15 d 9 h 30 min';
//每月15号9点半
select date_trunc('day',now()) + interval '9 h';
//每天9点
select date_trunc('day',now()) + interval '7 d';
//每周的今天
select date_trunc('weak',now())  + interval '1d 1minute';
//每周的周二第一分钟
select date_trunc('h',now()) + interval '30 minute';
//每小时
select date_trunc('minute',now()) + interval '30 second';
//每分钟
select date_trunc('minute',now()) + interval '30 minute 30 second';
//每30分钟
select date_trunc('quarter',now()) + interval '15 d 15 h 15 minute 30 second';
//本季度的第15天,15小时 15分 30秒
select date_trunc('quarter',now() ) - interval '1 h';
//每个季度最后一天的晚上11点
select date_trunc('quarter',now() + interval '3 month') - interval '1 h';
//每个季度的最后一天的晚上的11点(从下个季度开始算起).