需要帮助来获取oracle中多个记录的两个日期范围之间的日期

Question

您好，请您帮我解决一下这个问题

我有一张这样的表

     From_date    to_date       price Product
     13-Apr-2012  15-Apr-2012   15    hammer
     1-may-2012   7-May-2012    15    Scredriver 
    

从这个表中，我应该派生一个新的字段calc_date - 它应该包含from_date和to_date之间的日期，每一行都要复制价格和产品数据

结果集：

   From_date    to_date       calc_date     price     Product
     13-Apr-2012  15-Apr-2012  13-Apr-2012   15          hammer
     13-Apr-2012  15-Apr-2012  14-Apr-2012   15          hammer
     13-Apr-2012  15-Apr-2012  15-Apr-2012   15          hammer
     1-may-2012   5-May-2012    1-may-2012   15        Scredriver 
     1-may-2012   5-May-2012    2-may-2012   15        Scredriver 
     1-may-2012   5-May-2012    3-may-2012   15        Scredriver
     1-may-2012   5-May-2012    4-may-2012   15        Scredriver
     1-may-2012   5-May-2012    5-may-2012   15        Scredriver   

我尝试的Sql没有获取所需的数据（结果集）

      SELECT from_date,
           TO_DATE,
           from_date + (LEVEL - 1) AS calc_date,
           price,
           product
      FROM (SELECT from_date,
                   TO_DATE,
                   price,
                   product
              FROM details)
CONNECT BY LEVEL <= TO_DATE - (from_date - 1)

你能帮我查询一下，它提供了上面提到的理想结果集

Answer 1

我倾向于建立一个足够大的数字表，然后使用它：

with numbers as (
      select level - 1 as n
      from dual
      connect by level <= 500
     )
select from_date, to_date, from_date + n.n as calc_date, price, product
from details d join
     numbers n
     on n.n <= to_date - from_date;

您也可以为每条记录执行此操作。我发现这更容易理解。

如果您担心范围，可以这样做：

with numbers as (
      select level - 1 as n
      from dual
      connect by level <= (select max(to_date - from_date) + 1 from details)
     )
select from_date, to_date, from_date + n.n as calc_date, price, product
from details d join
     numbers n
     on n.n <= to_date - from_date;