Oracle在一个月内获得所有日期

Question

我正在尝试编写一个SQL语句,它允许我检索在9月份创建的所有订单而没有太多运气.

不工作:

select order_number, created_date
from orders
where created_date in to_date('2012-09', 'YYYY-MM');

工作但太长:

select order_number, created_date
from orders
where trunc(created_date) between to_date('2012-09-01', 'YYYY-MM-DD') and to_date('2012-09-30', 'YYYY-MM-DD');

Answer 1

怎么样:

select order_number, created_date
from orders
where created_date >= to_date('2012-09-01', 'YYYY-MM-DD') 
and created_date < to_date('2012-10-01', 'YYYY-MM-DD');

您应该尝试created_date保持不变,以确保您可以很好地利用它上面的索引.