Question

以下是一个示例查询：

select acct_no, month, sum(amount), substr(charge_type, 1, 3),
       case when (charge_type in ('CRE1', 'CRE2')
            then 'electronic payment'
            else 'cash'
       end as 'payment_type'
from   billing_data
where  charge_type in ('CRE1', 'CRE2', 'CASH')
group  by acct_no, month, sum(amount), 
          substr(charge_type, 1, 3)
having sum(amount) != 0
order  by acct_no asc;

我想要实现的是返回每个帐号组合在一起的CRE1和CRE2费用类型金额的总和，其中该总和不是0.

如果没有group by中的substr，查询将运行并返回预期结果除之外，CRE1和CRE2费用类型不会在一行中汇总。

当我在group by中添加substr时，我收到以下错误消息：

[Error] Execution (63: 15): ORA-00979: not a GROUP BY expression

有没有办法在Oracle中实现这一目标？

编辑：对于可能会遇到此帖子的任何人。解决方案如下：

select acct_no, month, sum(amount) as sumofamount, 
       substr(charge_type, 1, 3) as charge_type_substring,
       (
       case when (charge_type in ('CRE1', 'CRE2')
            then 'electronic payment'
            else 'cash'
       end) as payment_type
from   billing_data
where  charge_type in ('CRE1', 'CRE2', 'CASH')
group  by acct_no, month, substr(charge_type, 1, 3), 
       (
       case when (charge_type in ('CRE1', 'CRE2')
            then 'electronic payment'
            else 'cash'
       end)
       having sum(amount) != 0
order  by acct_no asc;

Answer 1

我相信你会这样：

select acct_no, month, sum(amount) as sumofamount, substr(charge_type, 1, 3) as charge_type_substring,
       case when (charge_type in ('CRE1', 'CRE2')
            then 'electronic payment'
            else 'cash'
       end as 'payment_type'
from   billing_data
where  charge_type in ('CRE1', 'CRE2', 'CASH')
group  by acct_no, month, charge_type_substring, payment_type
having sum(amount) != 0
order  by acct_no asc;

我对你的列别名采取了一些自由。这里最重要的一点是，sum()不属于您的组，因为我们正在使用公式聚合该列，但CASE语句的别名属于您的组，因为它没有被聚合一个公式。

Answer 2

聚合函数不属于GROUP BY。

您可以通过查看charge_type的前三个字母来解决您的问题：

select acct_no, month, sum(amount), substr(charge_type, 1, 3),
       (case when substr(charge_type, 1, 3) = 'CRE'
             then 'electronic payment'
             else 'cash'
        end) as payment_type
from  billing_data
where charge_type in ('CRE1', 'CRE2', 'CASH')
group by acct_no, month, substr(charge_type, 1, 3)
having sum(amount) <> 0
order by acct_no asc;

在Oracle

2 个答案: