MS SQL如何選擇最後N個記錄相同的客戶端

Question

我有一個由ClientID，ActionDate，Action和Result組成的表。

我需要選擇具有特定日期範圍內的特定操作/結果組合的不同客戶端。

舉例說明：

1. 我需要不同的clientId，其最近5動作/結果是呼叫/無應答。
2. 我需要在過去30天內只有Call/NoAnswer的獨特clientID。

感謝

Answer 1

1.

select ClientID from 
(
select 
    ClientID, 
    Action, 
    Result, 
    row_number() over (partition by ClientID order by ActionDate desc) as num 
from ClientActions 
) T -- the latest 5 action/result 
where rnum <= 5 
group by ClientID 
having MAX(case when Action='Call' and Result = 'NoAnswer' then 0 else 1 end) = 0 

2.

select ClientID 
from ClientActions 
where DATEDIFF(DAY, ActionDate, GETDATE()) <= 30 
group by ClientID 
having MAX(case when Action='Call' and Result = 'NoAnswer' then 0 else 1 end) = 0