如果超過一週的x天，則返回

Question

我有一張表，其中包含每天和每位客戶的交易清單。我需要在6個月的週期內找到週日交易次數超過x次的客戶/交易日期。

請注意，每個客戶每天可能有超過1筆交易，但只要他們在週日有1筆交易，那麼該週日就會計入6個月期間的週日計數。

這是我到目前爲止的代碼。我用的總和（transactionvalue）作爲天相結合可能的多筆交易的方法爲1次的記錄：

select customernumber,sum(transactionvalue),date from transactions 
where date between '2015-01-01' and '2015-06-01' 
and datename(weekday, date) = 'Sunday' 
group by customernumber,date 
having count(date) >= x 

然而，當我改變計數值，即「X」變大，記錄給定客戶變小。如果客戶在這段時間內有7個星期日，那麼我希望返回7條記錄，無論x是1還是7.只有當x大於7時，該客戶的所有交易纔會被退回。

下面是一些示例數據：

+-----------------+------------+--------------------+ 
| Customer Number | Date  | Transaction Amount | 
+-----------------+------------+--------------------+ 
| 1    | 17/05/2015 | 11.00    | 
| 2    | 17/05/2015 | 21.00    | 
| 2    | 17/05/2015 | 22.00    | 
| 3    | 17/05/2015 | 31.00    | 
| 3    | 17/05/2015 | 32.00    | 
| 3    | 17/05/2015 | 33.00    | 
| 1    | 24/05/2015 | 11.00    | 
| 2    | 24/05/2015 | 21.00    | 
| 3    | 24/05/2015 | 31.00    | 
| 2    | 31/05/2015 | 21.00    | 
+-----------------+------------+--------------------+ 

在這個例子中我期待具有以下返回如果x = 1：

+-----------------+------------+--------------------+ 
| Customer Number | Date  | Transaction Amount | 
+-----------------+------------+--------------------+ 
| 1    | 17/05/2015 | 11.00    | 
| 2    | 17/05/2015 | 43.00    | 
| 3    | 17/05/2015 | 96.00    | 
| 1    | 24/05/2015 | 11.00    | 
| 2    | 24/05/2015 | 21.00    | 
| 3    | 24/05/2015 | 31.00    | 
| 2    | 31/05/2015 | 21.00    | 
+-----------------+------------+--------------------+ 

但這返回如果x = 3：

+-----------------+------------+--------------------+ 
| Customer Number | Date  | Transaction Amount | 
+-----------------+------------+--------------------+ 
| 2    | 17/05/2015 | 43.00    | 
| 2    | 24/05/2015 | 21.00    | 
| 2    | 31/05/2015 | 21.00    | 
+-----------------+------------+--------------------+ 

感謝

Answer 1

試試這個：

select customernumber, date, sum(transactionvalue) as transaction_amt 
from transactions 
where date >= '2015-01-01' and date < '2015-07-01' 
    and datename(weekday, date) = 'Sunday' 
and customernumber in (
    select customernumber 
    from transactions 
    where date >= '2015-01-01' and date < '2015-07-01' 
     and datename(weekday, date) = 'Sunday' 
    group by customernumber 
    having count(distinct date) >= 3 
)  
group by customernumber, date 

SQL Fiddle