pg查询时间间隔（timestamp类型）

create_date timestamp(6) without time zone

1.从2015-10-12到2015-10-13 之间的4点到9点的数据

select * from schedule where create_date between to_date('2015-10-12','yyyy-MM-dd') and to_date('2015-10-13','yyyy-MM-dd') and EXTRACT(hour from create_date) between 4 and 9;

结果：

2.2015-10-12五点的数据

select * from schedule where hospital_id='syzyyadmin' and date_trunc('hour',create_date)=to_timestamp('2015-10-12 05','YYYY-MM-DD HH24')

结果：