oracle sql内部连接按月

Question

我有一个所选帐户的列表和一个帐户记录表（可能在所选列表中，也可能不在所选列表中），跨越 40 个月。我可以选择在表格中至少出现一次的所有选定帐户，但我还想查看所有 40 个月中出现的帐户。就像，我希望做类似于out join partition by 的事情，除了我想要更小的数据集。

我该怎么做？谢谢！

示例：

select distinct table1.acct_no
from table1
inner join selectedAcct
 on table1.acct_no = selectedAcct.acct_no

Answer 1

类似的东西（未编译/测试）：

with acct_month_list as
(
   -- get list of accts/months with missing months
   -- as null
   select distinct a.acctno, m.monno
   from   acctrecs a, mons m
   where  m.monno = a.monno(+)
)
select a2.acctno
from   accounts a2
where not exists ( -- any accounst with a null monno have a missing
                   -- month
                   select null
                   from   acct_month_list al 
                   where  al.acctno = a2.acctno
                   and    a1.monno is null )
and  exists ( -- ignore ones that have no records at all
              select null
              from   acctrecs ar
              where  ar.acctno = a2.acctno )