在我的查询中，我使用rownumber在客户ID上有一个分区，但我希望它按照emailaddress分组。有办法吗？
我有两个表，包含以下列：
顾客：
<ion-card *ngFor="let cData of CList" [style.background]="cData.Color">
<!-- -->
</ion-card>
订单：
EmailAddress,CustomerId
OrderDate,CustomerId,OrderId,PaymentAmount注意：我的数据在select
t.EmailAddress,
COUNT(t.OrderID) AS NumOrders,
SUM(t.PaymentAmount) as Total_Ordered,
max (case when t.rn = 2 then t.OrderDate end) as previous_date,
max (case when t.rn = 1 then t.Orderdate end) as last_date
from
(
select
c.EmailAddress,
o.OrderDate,
o.OrderID ,
o.PaymentAmount,
row_number() over (partition by c.CustomerID order by OrderDate desc) as rn
from
Customers c
Join Orders o
ON c.CustomerID=o.CustomerID
)t
group by
t.EmailAddress;
时是唯一的，而不是EmailAddress